when akka starts, use akkas default classloader (current thread)
use threads classloader when deserializing task results; classnotfoundexception includes classloader
Remove unused addIfNoPort.
Merge pull request #611 from squito/classloader

Use default classloaders for akka & deserializing task results
Merge pull request #626 from stephenh/remove-add-if-no-port

Remove unused addIfNoPort.
Skip fetching zero-sized blocks in OIO.
Also unify splitLocalRemoteBlocks for netty/nio and add a test case
Merge pull request #628 from shivaram/zero-block-size

Skip fetching zero-sized blocks in NIO.
Merge branch 'master' of git://github.com/mesos/spark

Conflicts:
	core/src/test/scala/spark/ShuffleSuite.scala