GIRAPH-581: More flexible Hive output (majakabiljo)
GIRAPH-587: Refactor configuration options (nitay)
GIRAPH-588: GIRAPH-588: More flexible Hive input (majakabiljo)
Merge remote-tracking branch 'origin/trunk' into auto-reuse

Conflicts:
	giraph-core/src/main/java/org/apache/giraph/conf/GiraphConfiguration.java
	giraph-hive/src/main/java/org/apache/giraph/hive/HiveGiraphRunner.java
bugfix