String interpolation + some other small changes

After having been invited to make the change in https://github.com/apache/spark/commit/6bee01dd04ef73c6b829110ebcdd622d521ea8ff#commitcomment-6284165 by @witgo.

Author: Jacek Laskowski <jacek@japila.pl>

Closes #748 from jaceklaskowski/sparkenv-string-interpolation and squashes the following commits:

be6ebac [Jacek Laskowski] String interpolation + some other small changes
[SPARK-1696][MLLIB] use alpha in dense dspr

It doesn't affect existing code because only `alpha = 1.0` is used in the code.

Author: Xiangrui Meng <meng@databricks.com>

Closes #778 from mengxr/mllib-dspr-fix and squashes the following commits:

a37402e [Xiangrui Meng] use alpha in dense dspr
[Typo] propertes -> properties

Author: andrewor14 <andrewor14@gmail.com>

Closes #780 from andrewor14/submit-typo and squashes the following commits:

e70e057 [andrewor14] propertes -> properties
[SPARK-1826] fix the head notation of package object dsl

Author: wangfei <scnbwf@yeah.net>

Closes #765 from scwf/dslfix and squashes the following commits:

d2d1a9d [wangfei] Update package.scala
66ff53b [wangfei] fix the head notation of package object dsl
default task number misleading in several places

  private[streaming] def defaultPartitioner(numPartitions: Int = self.ssc.sc.defaultParallelism){
    new HashPartitioner(numPartitions)
  }

it represents that the default task number in Spark Streaming relies on the variable defaultParallelism in SparkContext, which is decided by the config property spark.default.parallelism

the property "spark.default.parallelism" refers to https://github.com/apache/spark/pull/389

Author: Chen Chao <crazyjvm@gmail.com>

Closes #766 from CrazyJvm/patch-7 and squashes the following commits:

0b7efba [Chen Chao] Update streaming-programming-guide.md
cc5b66c [Chen Chao] default task number misleading in several places
[SPARK-1840] SparkListenerBus prints out scary error message when terminated normally

Running SparkPi example gave this error.
```
Pi is roughly 3.14374
14/05/14 18:16:19 ERROR Utils: Uncaught exception in thread SparkListenerBus
scala.runtime.NonLocalReturnControl$mcV$sp
```
This is due to the catch-all in the SparkListenerBus, which logged control throwable used by scala system

Author: Tathagata Das <tathagata.das1565@gmail.com>

Closes #783 from tdas/controlexception-fix and squashes the following commits:

a466c8d [Tathagata Das] Ignored control exceptions when logging all exceptions.
Add language tabs and Python version to interactive part of quick-start

This is an addition of some stuff that was missed in https://issues.apache.org/jira/browse/SPARK-1567. I've also updated the doc to show submitting the Python application with spark-submit.

Author: Matei Zaharia <matei@databricks.com>

Closes #782 from mateiz/spark-1567-extra and squashes the following commits:

6f8f2aa [Matei Zaharia] tweaks
9ed9874 [Matei Zaharia] tweaks
ae67c3e [Matei Zaharia] tweak
b303ba3 [Matei Zaharia] tweak
1433a4d [Matei Zaharia] Add language tabs and Python version to interactive part of quick-start guide
Documentation: Encourage use of reduceByKey instead of groupByKey.

Author: Patrick Wendell <pwendell@gmail.com>

Closes #784 from pwendell/group-by-key and squashes the following commits:

9b4505f [Patrick Wendell] Small fix
6347924 [Patrick Wendell] Documentation: Encourage use of reduceByKey instead of groupByKey.
Package docs

This is a few changes based on the original patch by @scrapcodes.

Author: Prashant Sharma <prashant.s@imaginea.com>
Author: Patrick Wendell <pwendell@gmail.com>

Closes #785 from pwendell/package-docs and squashes the following commits:

c32b731 [Patrick Wendell] Changes based on Prashant's patch
c0463d3 [Prashant Sharma] added eof new line
ce8bf73 [Prashant Sharma] Added eof new line to all files.
4c35f2e [Prashant Sharma] SPARK-1563 Add package-info.java and package.scala files for all packages that appear in docs
fix different versions of commons-lang dependency and apache/spark#746 addendum

Author: witgo <witgo@qq.com>

Closes #754 from witgo/commons-lang and squashes the following commits:

3ebab31 [witgo] merge master
f3b8fa2 [witgo] merge master
2083fae [witgo] repeat definition
5599cdb [witgo] multiple version of sbt  dependency
c1b66a1 [witgo] fix different versions of commons-lang dependency
HOTFIX: Don't build Javadoc in Maven when creating releases.

Because we've added java package descriptions in some packages that don't
have any Java files, running the Javadoc target hits this issue:

http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4492654

To fix this I've simply removed the javadoc target when publishing
releases.
SPARK-1846 Ignore logs directory in RAT checks

https://issues.apache.org/jira/browse/SPARK-1846

Author: Andrew Ash <andrew@andrewash.com>

Closes #793 from ash211/SPARK-1846 and squashes the following commits:

3f50db5 [Andrew Ash] SPARK-1846 Ignore logs directory in RAT checks
[SPARK-1845] [SQL] Use AllScalaRegistrar for SparkSqlSerializer to register serializers of ...

...Scala collections.

When I execute `orderBy` or `limit` for `SchemaRDD` including `ArrayType` or `MapType`, `SparkSqlSerializer` throws the following exception:

```
com.esotericsoftware.kryo.KryoException: Class cannot be created (missing no-arg constructor): scala.collection.immutable.$colon$colon
```

or

```
com.esotericsoftware.kryo.KryoException: Class cannot be created (missing no-arg constructor): scala.collection.immutable.Vector
```

or

```
com.esotericsoftware.kryo.KryoException: Class cannot be created (missing no-arg constructor): scala.collection.immutable.HashMap$HashTrieMap
```

and so on.

This is because registrations of serializers for each concrete collections are missing in `SparkSqlSerializer`.
I believe it should use `AllScalaRegistrar`.
`AllScalaRegistrar` covers a lot of serializers for concrete classes of `Seq`, `Map` for `ArrayType`, `MapType`.

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #790 from ueshin/issues/SPARK-1845 and squashes the following commits:

d1ed992 [Takuya UESHIN] Use AllScalaRegistrar for SparkSqlSerializer to register serializers of Scala collections.
[SPARK-1819] [SQL] Fix GetField.nullable.

`GetField.nullable` should be `true` not only when `field.nullable` is `true` but also when `child.nullable` is `true`.

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #757 from ueshin/issues/SPARK-1819 and squashes the following commits:

8781a11 [Takuya UESHIN] Modify a test to use named parameters.
5bfc77d [Takuya UESHIN] Fix GetField.nullable.
[SPARK-1741][MLLIB] add predict(JavaRDD) to RegressionModel, ClassificationModel, and KMeans

`model.predict` returns a RDD of Scala primitive type (Int/Double), which is recognized as Object in Java. Adding predict(JavaRDD) could make life easier for Java users.

Added tests for KMeans, LinearRegression, and NaiveBayes.

Will update examples after https://github.com/apache/spark/pull/653 gets merged.

cc: @srowen

Author: Xiangrui Meng <meng@databricks.com>

Closes #670 from mengxr/predict-javardd and squashes the following commits:

b77ccd8 [Xiangrui Meng] Merge branch 'master' into predict-javardd
43caac9 [Xiangrui Meng] add predict(JavaRDD) to RegressionModel, ClassificationModel, and KMeans