Merge pull request #272 from tmyklebu/master

Track and report task result serialisation time.

 - DirectTaskResult now has a ByteBuffer valueBytes instead of a T value.
 - DirectTaskResult now has a member function T value() that deserialises valueBytes.
 - Executor serialises value into a ByteBuffer and passes it to DTR's ctor.
 - Executor tracks the time taken to do so and puts it in a new field in TaskMetrics.
 - StagePage now reports serialisation time from TaskMetrics along with the other things it reported.
Un-semicolon PythonMLLibAPI.
Bindings for linear, Lasso, and ridge regression.
Python side of python bindings for linear, Lasso, and ridge regression
Split GraphSuite; simplify LocalSparkContext
Split VertexRDD tests; fix #114
Split AnalyticsSuite into algorithms suites
Scala classification and clustering stubs; matrix serialization/deserialization.
Python stubs for classification and clustering.
Merge pull request #1 from aarondav/127

Merge master into 127
Merge pull request #115 from ankurdave/test-reorg

Reorganize unit tests; improve GraphSuite test coverage
Tests for the Python side of the mllib bindings.
Remove gigantic endian-specific test and exception tests.
Whitespace.
Licence notice.
Change some docstrings and add some others.
Un-semicolon mllib.py.
Javadocs; also, declare some things private.
Write mapTriplets test
Added tests for PartitionerAwareUnionRDD in the CheckpointSuite. Refactored CheckpointSuite to make the tests simpler and more reliable. Added missing test for ZippedRDD.