Fix spark-submit path in spark-shell & pyspark

Author: Neville Li <neville@spotify.com>

Closes #812 from nevillelyh/neville/v1.0 and squashes the following commits:

0dc33ed [Neville Li] Fix spark-submit path in pyspark
becec64 [Neville Li] Fix spark-submit path in spark-shell
SPARK-1873: Add README.md file when making distributions

Author: Patrick Wendell <pwendell@gmail.com>

Closes #818 from pwendell/reamde and squashes the following commits:

4020b11 [Patrick Wendell] SPARK-1873: Add README.md file when making distributions
[WIP][SPARK-1871][MLLIB] Improve MLlib guide for v1.0

Some improvements to MLlib guide:

1. [SPARK-1872] Update API links for unidoc.
2. [SPARK-1783] Added `page.displayTitle` to the global layout. If it is defined, use it instead of `page.title` for title display.
3. Add more Java/Python examples.

Author: Xiangrui Meng <meng@databricks.com>

Closes #816 from mengxr/mllib-doc and squashes the following commits:

ec2e407 [Xiangrui Meng] format scala example for ALS
cd9f40b [Xiangrui Meng] add a paragraph to summarize distributed matrix types
4617f04 [Xiangrui Meng] add python example to loadLibSVMFile and fix Java example
d6509c2 [Xiangrui Meng] [SPARK-1783] update mllib titles
561fdc0 [Xiangrui Meng] add a displayTitle option to global layout
195d06f [Xiangrui Meng] add Java example for summary stats and minor fix
9f1ff89 [Xiangrui Meng] update java api links in mllib-basics
7dad18e [Xiangrui Meng] update java api links in NB
3a0f4a6 [Xiangrui Meng] api/pyspark -> api/python
35bdeb9 [Xiangrui Meng] api/mllib -> api/scala
e4afaa8 [Xiangrui Meng] explicity state what might change
[SPARK-1876] Windows fixes to deal with latest distribution layout changes

- Look for JARs in the right place
- Launch examples the same way as on Unix
- Load datanucleus JARs if they exist
- Don't attempt to parse local paths as URIs in SparkSubmit, since paths with C:\ are not valid URIs
- Also fixed POM exclusion rules for datanucleus (it wasn't properly excluding it, whereas SBT was)

Author: Matei Zaharia <matei@databricks.com>

Closes #819 from mateiz/win-fixes and squashes the following commits:

d558f96 [Matei Zaharia] Fix comment
228577b [Matei Zaharia] Review comments
d3b71c7 [Matei Zaharia] Properly exclude datanucleus files in Maven assembly
144af84 [Matei Zaharia] Update Windows scripts to match latest binary package layout
SPARK-1878: Fix the incorrect initialization order

JIRA: https://issues.apache.org/jira/browse/SPARK-1878

Author: zsxwing <zsxwing@gmail.com>

Closes #822 from zsxwing/SPARK-1878 and squashes the following commits:

4a47e27 [zsxwing] SPARK-1878: Fix the incorrect initialization order
SPARK-1879. Increase MaxPermSize since some of our builds have many classes

See https://issues.apache.org/jira/browse/SPARK-1879 -- builds with Hadoop2 and Hive ran out of PermGen space in spark-shell, when those things added up with the Scala compiler.

Note that users can still override it by setting their own Java options with this change. Their options will come later in the command string than the -XX:MaxPermSize=128m.

Author: Matei Zaharia <matei@databricks.com>

Closes #823 from mateiz/spark-1879 and squashes the following commits:

6bc0ee8 [Matei Zaharia] Increase MaxPermSize to 128m since some of our builds have lots of classes
[SPARK-1875]NoClassDefFoundError: StringUtils when building with hadoop 1.x and hive

Author: witgo <witgo@qq.com>

Closes #824 from witgo/SPARK-1875_commons-lang-2.6 and squashes the following commits:

ef7231d [witgo] review commit
ead3c3b [witgo] SPARK-1875:NoClassDefFoundError: StringUtils when building against Hadoop 1