Addressing bug in BitSet.setUntil(ind)

Addressing bug in BitSet.setUntil(ind) where if invoked with a multiple of 64 could lead to an index out of bounds error.

Changing image references to master branch.

Cleanup of VertexSetRDD

Shuffle replicated vertex attributes efficiently in columnar format

Specialize mapReduceTriplets for accessing subsets of vertex attributes

ByteCodeUtils.invokedMethod(), which we use in mapReduceTriplets, throws
a ClassNotFoundException when called with a closure defined in the
console. This commit catches the exception and conservatively assumes
the closure references all edge attributes.

Looks good to me.

Kryo messages

Conflicts:
	graph/src/main/scala/org/apache/spark/graph/impl/GraphImpl.scala

GraphX Console with Logo Text

Changing Pregel API to use mapReduceTriplets instead of aggregateNeighbors

Changing Pregel API to operate directly on edge triplets in SendMessage rather than (Vid, EdgeTriplet) pairs.

Converted for loops to while loops in EdgePartition.

Added GraphX to classpath.

Reverting to Array based (materialized) output in VertexSetRDD