Preparing development version 1.2.1-SNAPSHOT
HOTFIX: Rolling back incorrect version change
[SPARK-4597] Use proper exception and reset variable in Utils.createTempDir()

`File.exists()` and `File.mkdirs()` only throw `SecurityException` instead of `IOException`. Then, when an exception is thrown, `dir` should be reset too.

Author: Liang-Chi Hsieh <viirya@gmail.com>

Closes #3449 from viirya/fix_createtempdir and squashes the following commits:

36cacbd [Liang-Chi Hsieh] Use proper exception and reset variable.

(cherry picked from commit 49fe8797e64f10c574e0790b32a8c3fdc7e594a0)
Signed-off-by: Josh Rosen <joshrosen@databricks.com>
[DOCS][BUILD] Add instruction to use change-version-to-2.11.sh in 'Building for Scala 2.11'.

To build with Scala 2.11, we have to execute `change-version-to-2.11.sh` before Maven execute, otherwise inter-module dependencies are broken.

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

Closes #3361 from ueshin/docs/building-spark_2.11 and squashes the following commits:

1d29126 [Takuya UESHIN] Add instruction to use change-version-to-2.11.sh in 'Building for Scala 2.11'.

(cherry picked from commit 0fcd24cc542040ff3555290eec7b021062e7e6ac)
Signed-off-by: Patrick Wendell <pwendell@gmail.com>
SPARK-2143 [WEB UI] Add Spark version to UI footer

This PR adds the Spark version number to the UI footer; this is how it looks:

![screen shot 2014-11-21 at 22 58 40](https://cloud.githubusercontent.com/assets/822522/5157738/f4822094-7316-11e4-98f1-333a535fdcfa.png)

Author: Sean Owen <sowen@cloudera.com>

Closes #3410 from srowen/SPARK-2143 and squashes the following commits:

e9b3a7a [Sean Owen] Add Spark version to footer
[SPARK-4656][Doc] Typo in Programming Guide markdown

Grammatical error in Programming Guide document

Author: lewuathe <lewuathe@me.com>

Closes #3412 from Lewuathe/typo-programming-guide and squashes the following commits:

a3e2f00 [lewuathe] Typo in Programming Guide markdown

(cherry picked from commit a217ec5fd5cd7addc69e538d6ec6dd64956cc8ed)
Signed-off-by: Josh Rosen <joshrosen@databricks.com>
[DOC] Fixes formatting typo in SQL programming guide

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Author: Cheng Lian <lian@databricks.com>

Closes #3498 from liancheng/fix-sql-doc-typo and squashes the following commits:

865ecd7 [Cheng Lian] Fixes formatting typo in SQL programming guide

(cherry picked from commit 2a4d389f70b2066b1ac32b081bef44e61fefb03c)
Signed-off-by: Josh Rosen <joshrosen@databricks.com>
SPARK-2192 [BUILD] Examples Data Not in Binary Distribution

Simply, add data/ to distributions. This adds about 291KB (compressed) to the tarball, FYI.

Author: Sean Owen <sowen@cloudera.com>

Closes #3480 from srowen/SPARK-2192 and squashes the following commits:

47688f1 [Sean Owen] Add data/ to distributions

(cherry picked from commit 6384f42ab2e5c2b3e767ab4a428cda20a8ddcbe1)
Signed-off-by: Xiangrui Meng <meng@databricks.com>
[SPARK-4661][Core] Minor code and docs cleanup

Author: zsxwing <zsxwing@gmail.com>

Closes #3521 from zsxwing/SPARK-4661 and squashes the following commits:

03cbe3f [zsxwing] Minor code and docs cleanup

(cherry picked from commit 30a86acdefd5428af6d6264f59a037e0eefd74b4)
Signed-off-by: Reynold Xin <rxin@databricks.com>
Documentation: add description for repartitionAndSortWithinPartitions

Author: Madhu Siddalingaiah <madhu@madhu.com>

Closes #3390 from msiddalingaiah/master and squashes the following commits:

cbccbfe [Madhu Siddalingaiah] Documentation: replace <b> with <code> (again)
332f7a2 [Madhu Siddalingaiah] Documentation: replace <b> with <code>
cd2b05a [Madhu Siddalingaiah] Merge remote-tracking branch 'upstream/master'
0fc12d7 [Madhu Siddalingaiah] Documentation: add description for repartitionAndSortWithinPartitions

(cherry picked from commit 2b233f5fc4beb2c6ed4bc142e923e96f8bad3ec4)
Signed-off-by: Josh Rosen <joshrosen@databricks.com>
[SPARK-4258][SQL][DOC] Documents spark.sql.parquet.filterPushdown

Documents `spark.sql.parquet.filterPushdown`, explains why it's turned off by default and when it's safe to be turned on.

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Author: Cheng Lian <lian@databricks.com>

Closes #3440 from liancheng/parquet-filter-pushdown-doc and squashes the following commits:

2104311 [Cheng Lian] Documents spark.sql.parquet.filterPushdown

(cherry picked from commit 5db8dcaf494e0dffed4fc22f19b0334d95ab6bfb)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SQL] add @group tab in limit() and count()

group tab is missing for scaladoc

Author: Jacky Li <jacky.likun@gmail.com>

Closes #3458 from jackylk/patch-7 and squashes the following commits:

0121a70 [Jacky Li] add @group tab in limit() and count()

(cherry picked from commit bafee67ebad01f7aea2cd393a70b57eb8345eeb0)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SPARK-4358][SQL] Let BigDecimal do checking type compatibility

Remove hardcoding max and min values for types. Let BigDecimal do checking type compatibility.

Author: Liang-Chi Hsieh <viirya@gmail.com>

Closes #3208 from viirya/more_numericLit and squashes the following commits:

e9834b4 [Liang-Chi Hsieh] Remove byte and short types for number literal.
1bd1825 [Liang-Chi Hsieh] Fix Indentation and make the modification clearer.
cf1a997 [Liang-Chi Hsieh] Modified for comment to add a rule of analysis that adds a cast.
91fe489 [Liang-Chi Hsieh] add Byte and Short.
1bdc69d [Liang-Chi Hsieh] Let BigDecimal do checking type compatibility.

(cherry picked from commit b57365a1ec89e31470f424ff37d5ebc7c90a39d8)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SPARK-4650][SQL] Supporting multi column support in countDistinct function like count(distinct c1,c2..) in Spark SQL

Supporting multi column support in countDistinct function like count(distinct c1,c2..) in Spark SQL

Author: ravipesala <ravindra.pesala@huawei.com>
Author: Michael Armbrust <michael@databricks.com>

Closes #3511 from ravipesala/countdistinct and squashes the following commits:

cc4dbb1 [ravipesala] style
070e12a [ravipesala] Supporting multi column support in count(distinct c1,c2..) in Spark SQL

(cherry picked from commit 6a9ff19dc06745144d5b311d4f87073c81d53a8f)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SPARK-4658][SQL] Code documentation issue in DDL of datasource API

Author: ravipesala <ravindra.pesala@huawei.com>

Closes #3516 from ravipesala/ddl_doc and squashes the following commits:

d101fdf [ravipesala] Style issues fixed
d2238cd [ravipesala] Corrected documentation

(cherry picked from commit bc353819cc86c3b0ad75caf81b47744bfc2aeeb3)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SQL] Minor fix for doc and comment

Author: wangfei <wangfei1@huawei.com>

Closes #3533 from scwf/sql-doc1 and squashes the following commits:

962910b [wangfei] doc and comment fix

(cherry picked from commit 7b79957879db4dfcc7c3601cb40ac4fd576259a5)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SQL][DOC] Date type in SQL programming guide

Author: Daoyuan Wang <daoyuan.wang@intel.com>

Closes #3535 from adrian-wang/datedoc and squashes the following commits:

18ff1ed [Daoyuan Wang] [DOC] Date type

(cherry picked from commit 5edbcbfb61703398a24ce5162a74aba04e365b0c)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SPARK-4529] [SQL] support view with column alias

Support view definition like

CREATE VIEW view3(valoo)
TBLPROPERTIES ("fear" = "factor")
AS SELECT upper(value) FROM src WHERE key=86;

[valoo as the alias of upper(value)]. This is missing part of SPARK-4239, for a fully view support.

Author: Daoyuan Wang <daoyuan.wang@intel.com>

Closes #3396 from adrian-wang/viewcolumn and squashes the following commits:

4d001d0 [Daoyuan Wang] support view with column alias

(cherry picked from commit 4df60a8cbc58f2877787245c2a83b2de85579c82)
Signed-off-by: Michael Armbrust <michael@databricks.com>
[SPARK-4611][MLlib] Implement the efficient vector norm

The vector norm in breeze is implemented by `activeIterator` which is known to be very slow.
In this PR, an efficient vector norm is implemented, and with this API, `Normalizer` and
`k-means` have big performance improvement.

Here is the benchmark against mnist8m dataset.

a) `Normalizer`
Before
DenseVector: 68.25secs
SparseVector: 17.01secs

With this PR
DenseVector: 12.71secs
SparseVector: 2.73secs

b) `k-means`
Before
DenseVector: 83.46secs
SparseVector: 61.60secs

With this PR
DenseVector: 70.04secs
SparseVector: 59.05secs

Author: DB Tsai <dbtsai@alpinenow.com>

Closes #3462 from dbtsai/norm and squashes the following commits:

63c7165 [DB Tsai] typo
0c3637f [DB Tsai] add import org.apache.spark.SparkContext._ back
6fa616c [DB Tsai] address feedback
9b7cb56 [DB Tsai] move norm to static method
0b632e6 [DB Tsai] kmeans
dbed124 [DB Tsai] style
c1a877c [DB Tsai] first commit

(cherry picked from commit 64f3175bf976f5a28e691cedc7a4b333709e0c58)
Signed-off-by: Xiangrui Meng <meng@databricks.com>
[SPARK-4686] Link to allowed master URLs is broken

The link points to the old scala programming guide; it should point to the submitting applications page.

This should be backported to 1.1.2 (it's been broken as of 1.0).

Author: Kay Ousterhout <kayousterhout@gmail.com>

Closes #3542 from kayousterhout/SPARK-4686 and squashes the following commits:

a8fc43b [Kay Ousterhout] [SPARK-4686] Link to allowed master URLs is broken

(cherry picked from commit d9a148ba6a67a01e4bf77c35c41dd4cbc8918c82)
Signed-off-by: Kay Ousterhout <kayousterhout@gmail.com>