GIRAPH-606: Configure classes by default when possible (apresta)
GIRAPH-609:  More information on runtime exceptions for Callables
GIRAPH-610: Simplify implementation of configurable VertexEdges (apresta)
GIRAPH-611: Vertex/EdgeReaderWrapper should configure inner reader (majakabiljo)
GIRAPH-527: readVertexInputSplit is always reporting 0 vertices and 0 edges (nitay)
Merge remote-tracking branch 'origin/trunk' into vertex-runner

Conflicts:
	CHANGELOG
updates