Deprecated and added a few java api methods for corresponding scala api.

PR [402](https://github.com/apache/incubator-spark/pull/402) from incubator repo.

Author: Prashant Sharma <prashant.s@imaginea.com>

Closes #19 from ScrapCodes/java-api-completeness and squashes the following commits:

11d0c2b [Prashant Sharma] Integer -> java.lang.Integer
737819a [Prashant Sharma] SPARK-1095 add explicit return types to APIs.
3ddc8bb [Prashant Sharma] Deprected *With functions in scala and added a few missing Java APIs
Updated link for pyspark examples in docs

Author: Jyotiska NK <jyotiska123@gmail.com>

Closes #22 from jyotiska/pyspark_docs and squashes the following commits:

426136c [Jyotiska NK] Updated link for pyspark examples
Remove references to ClusterScheduler (SPARK-1140)

ClusterScheduler was renamed to TaskSchedulerImpl; this commit
updates comments and tests accordingly.

Author: Kay Ousterhout <kayousterhout@gmail.com>

Closes #9 from kayousterhout/cluster_scheduler_death and squashes the following commits:

d6fd119 [Kay Ousterhout] Remove references to ClusterScheduler.
SPARK-1129: use a predefined seed when seed is zero in XORShiftRandom

If the seed is zero, XORShift generates all zeros, which would create unexpected result.

JIRA: https://spark-project.atlassian.net/browse/SPARK-1129

Author: Xiangrui Meng <meng@databricks.com>

Closes #645 from mengxr/xor and squashes the following commits:

1b086ab [Xiangrui Meng] use MurmurHash3 to set seed in XORShiftRandom
45c6f16 [Xiangrui Meng] minor style change
51f4050 [Xiangrui Meng] use a predefined seed when seed is zero in XORShiftRandom
SPARK-1121 Only add avro if the build is for Hadoop 0.23.X and SPARK_YARN is set

Author: Prashant Sharma <prashant.s@imaginea.com>

Closes #6 from ScrapCodes/SPARK-1121/avro-dep-fix and squashes the following commits:

9b29e34 [Prashant Sharma] Review feedback on PR
46ed2ad [Prashant Sharma] SPARK-1121-Only add avro if the build is for Hadoop 0.23.X and SPARK_YARN is set
[SPARK-1089] fix the regression problem on ADD_JARS in 0.9

https://spark-project.atlassian.net/browse/SPARK-1089

copied from JIRA, reported by @ash211

"Using the ADD_JARS environment variable with spark-shell used to add the jar to both the shell and the various workers. Now it only adds to the workers and importing a custom class in the shell is broken.
The workaround is to add custom jars to both ADD_JARS and SPARK_CLASSPATH.
We should fix ADD_JARS so it works properly again.
See various threads on the user list:
https://mail-archives.apache.org/mod_mbox/incubator-spark-user/201402.mbox/%3CCAJbo4neMLiTrnm1XbyqomWmp0m+EUcg4yE-txuRGSVKOb5KLeA@mail.gmail.com%3E
(another one that doesn't appear in the archives yet titled "ADD_JARS not working on 0.9")"

The reason of this bug is two-folds

in the current implementation of SparkILoop.scala, the settings.classpath is not set properly when the process() method is invoked

the weird behaviour of Scala 2.10, (I personally thought it is a bug)

if we simply set value of a PathSettings object (like settings.classpath), the isDefault is not set to true (this is a flag showing if the variable is modified), so it makes the PathResolver loads the default CLASSPATH environment variable value to calculated the path (see https://github.com/scala/scala/blob/2.10.x/src/compiler/scala/tools/util/PathResolver.scala#L215)

what we have to do is to manually make this flag set, (https://github.com/CodingCat/incubator-spark/blob/e3991d97ddc33e77645e4559b13bf78b9e68239a/repl/src/main/scala/org/apache/spark/repl/SparkILoop.scala#L884)

Author: CodingCat <zhunansjtu@gmail.com>

Closes #13 from CodingCat/SPARK-1089 and squashes the following commits:

8af81e7 [CodingCat] impose non-null settings
9aa2125 [CodingCat] code cleaning
ce36676 [CodingCat] code cleaning
e045582 [CodingCat] fix the regression problem on ADD_JARS in 0.9
Show Master status on UI page

For standalone HA mode, A status is useful to identify the current master, already in json format too.

Author: Raymond Liu <raymond.liu@intel.com>

Closes #24 from colorant/status and squashes the following commits:

df630b3 [Raymond Liu] Show Master status on UI page
SPARK 1084.1 (resubmitted)

(Ported from https://github.com/apache/incubator-spark/pull/637 )

Author: Sean Owen <sowen@cloudera.com>

Closes #31 from srowen/SPARK-1084.1 and squashes the following commits:

6c4a32c [Sean Owen] Suppress warnings about legitimate unchecked array creations, or change code to avoid it
f35b833 [Sean Owen] Fix two misc javadoc problems
254e8ef [Sean Owen] Fix one new style error introduced in scaladoc warning commit
5b2fce2 [Sean Owen] Fix scaladoc invocation warning, and enable javac warnings properly, with plugin config updates
007762b [Sean Owen] Remove dead scaladoc links
b8ff8cb [Sean Owen] Replace deprecated Ant <tasks> with <target>
[HOTFIX] Patching maven build after #6 (SPARK-1121).

That patch removed the Maven avro declaration but didn't remove the
actual dependency in core. /cc @scrapcodes

Author: Patrick Wendell <pwendell@gmail.com>

Closes #37 from pwendell/master and squashes the following commits:

0ef3008 [Patrick Wendell] [HOTFIX] Patching maven build after #6 (SPARK-1121).
Removed reference to incubation in Spark user docs.

Author: Reynold Xin <rxin@apache.org>

Closes #2 from rxin/docs and squashes the following commits:

08bbd5f [Reynold Xin] Removed reference to incubation in Spark user docs.
Remote BlockFetchTracker trait

This trait seems to have been created a while ago when there
were multiple implementations; now that there's just one, I think it
makes sense to merge it into the BlockFetcherIterator trait.

Author: Kay Ousterhout <kayousterhout@gmail.com>

Closes #39 from kayousterhout/remove_tracker and squashes the following commits:

8173939 [Kay Ousterhout] Remote BlockFetchTracker.
SPARK-1032. If Yarn app fails before registering, app master stays aroun...

...d long after

This reopens https://github.com/apache/incubator-spark/pull/648 against the new repo.

Author: Sandy Ryza <sandy@cloudera.com>

Closes #28 from sryza/sandy-spark-1032 and squashes the following commits:

5953f50 [Sandy Ryza] SPARK-1032. If Yarn app fails before registering, app master stays around long after
SPARK-1051. On YARN, executors don't doAs submitting user

This reopens https://github.com/apache/incubator-spark/pull/538 against the new repo

Author: Sandy Ryza <sandy@cloudera.com>

Closes #29 from sryza/sandy-spark-1051 and squashes the following commits:

708ce49 [Sandy Ryza] SPARK-1051. doAs submitting user in YARN
SPARK-1151: Update dev merge script to use spark.git instead of incubator-spark

Author: Thomas Graves <tgraves@apache.org>

Closes #47 from tgravescs/fix_merge_script and squashes the following commits:

8209ab1 [Thomas Graves] Update dev merge script to use spark.git instead of incubator-spark
[SPARK-979] Randomize order of offers.

This commit randomizes the order of resource offers to avoid scheduling
all tasks on the same small set of machines.

This is a much simpler solution to SPARK-979 than #7.

Author: Kay Ousterhout <kayousterhout@gmail.com>

Closes #27 from kayousterhout/randomize and squashes the following commits:

435d817 [Kay Ousterhout] [SPARK-979] Randomize order of offers.
[SPARK-1150] fix repo location in create script

https://spark-project.atlassian.net/browse/SPARK-1150

fix the repo location in create_release script

Author: Mark Grover <mark@apache.org>

Closes #48 from CodingCat/script_fixes and squashes the following commits:

01f4bf7 [Mark Grover] Fixing some nitpicks
d2244d4 [Mark Grover] SPARK-676: Abbreviation in SPARK_MEM but not in SPARK_WORKER_MEMORY
Revert "[SPARK-1150] fix repo location in create script"

This reverts commit 9aa095711858ce8670e51488f66a3d7c1a821c30.
[SPARK-1150] fix repo location in create script (re-open)

reopen for https://spark-project.atlassian.net/browse/SPARK-1150

Author: CodingCat <zhunansjtu@gmail.com>

Closes #52 from CodingCat/script_fixes and squashes the following commits:

fc05a71 [CodingCat] fix repo location in create script
[SPARK-1100] prevent Spark from overwriting directory silently

Thanks for Diana Carroll to report this issue (https://spark-project.atlassian.net/browse/SPARK-1100)

the current saveAsTextFile/SequenceFile will overwrite the output directory silently if the directory already exists, this behaviour is not desirable because

overwriting the data silently is not user-friendly

if the partition number of two writing operation changed, then the output directory will contain the results generated by two runnings

My fix includes:

add some new APIs with a flag for users to define whether he/she wants to overwrite the directory:
if the flag is set to true, then the output directory is deleted first and then written into the new data to prevent the output directory contains results from multiple rounds of running;

if the flag is set to false, Spark will throw an exception if the output directory already exists

changed JavaAPI part

default behaviour is overwriting

Two questions

should we deprecate the old APIs without such a flag?

I noticed that Spark Streaming also called these APIs, I thought we don't need to change the related part in streaming? @tdas

Author: CodingCat <zhunansjtu@gmail.com>

Closes #11 from CodingCat/SPARK-1100 and squashes the following commits:

6a4e3a3 [CodingCat] code clean
ef2d43f [CodingCat] add new test cases and code clean
ac63136 [CodingCat] checkOutputSpecs not applicable to FSOutputFormat
ec490e8 [CodingCat] prevent Spark from overwriting directory silently and leaving dirty directory
Initialized the regVal for first iteration in SGD optimizer

Ported from https://github.com/apache/incubator-spark/pull/633

In runMiniBatchSGD, the regVal (for 1st iter) should be initialized
as sum of sqrt of weights if it's L2 update; for L1 update, the same logic is followed.

It maybe not be important here for SGD since the updater doesn't take the loss
as parameter to find the new weights. But it will give us the correct history of loss.
However, for LBFGS optimizer we implemented, the correct loss with regVal is crucial to
find the new weights.

Author: DB Tsai <dbtsai@alpinenow.com>

Closes #40 from dbtsai/dbtsai-smallRegValFix and squashes the following commits:

77d47da [DB Tsai] In runMiniBatchSGD, the regVal (for 1st iter) should be initialized as sum of sqrt of weights if it's L2 update; for L1 update, the same logic is followed.