SPARK-1119 and other build improvements

1. Makes assembly and examples jar naming consistent in maven/sbt.
2. Updates make-distribution.sh to use Maven and fixes some bugs.
3. Updates the create-release script to call make-distribution script.

Author: Patrick Wendell <pwendell@gmail.com>

Closes #502 from pwendell/make-distribution and squashes the following commits:

1a97f0d [Patrick Wendell] SPARK-1119 and other build improvements
SPARK-1583: Fix a bug that using java.util.HashMap by mistake

JIRA: https://issues.apache.org/jira/browse/SPARK-1583

Does anyone know why using `java.util.HashMap` rather than `mutable.HashMap`? Some methods of `java.util.HashMap` are not generics and compiler can not help us find similar problems.

Author: zsxwing <zsxwing@gmail.com>

Closes #500 from zsxwing/SPARK-1583 and squashes the following commits:

7bfd74d [zsxwing] SPARK-1583: Fix a bug that using java.util.HashMap by mistake
SPARK-1572 Don't kill Executor if PythonRDD fails while computing parent

Previously, the behavior was that if the parent RDD threw any exception other than IOException or FileNotFoundException (which is quite possible for Hadoop input sources), the entire Executor would crash, because the default thread a uncaught exception handler calls System.exit().

This patch avoids two related issues:

  1. Always catch exceptions in this reader thread.
  2. Don't mask readerException when Python throws an EOFError
     after worker.shutdownOutput() is called.

Author: Aaron Davidson <aaron@databricks.com>

Closes #486 from aarondav/pyspark and squashes the following commits:

fbb11e9 [Aaron Davidson] Make sure FileNotFoundExceptions are handled same as before
b9acb3e [Aaron Davidson] SPARK-1572 Don't kill Executor if PythonRDD fails while computing parent
Honor default fs name when initializing event logger.

This is related to SPARK-1459 / PR #375. Without this fix,
FileLogger.createLogDir() may try to create the log dir on
HDFS, while createWriter() will try to open the log file on
the local file system, leading to interesting errors and
confusion.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #450 from vanzin/event-file-2 and squashes the following commits:

592cdb3 [Marcelo Vanzin] Honor default fs name when initializing event logger.