GIRAPH-720: Provide a way to change job name (majakabiljo)
GIRAPH-721: Don't call progress on each edge/vertex loaded (majakabiljo)
GIRAPH-701: Communication improvement using one-to-all message
sending (Bingjing via aching)
Rest of GIRAPH-701.
Merge branch 'trunk' of github.com:apache/giraph into GIRAPH-549