refoactoring zookeeper
rexster output format framework
add error throwing in case of missing of one of the two Input/Output Formats
GIRAPH-773
GIRAPH-786: XSparseVector create a lot of objects in add/write (ikabiljo via majakabiljo)
GIRAPH-787: Use HiveIO 1.9 (gmalewicz via aching)
GIRAPH-789: Upgrade hive-io to 0.20 - less metastore accesses (majakabiljo)
GIRAPH-790: Add a way to automatically retry a job (majakabiljo)
GIRAPH-791: HiveGiraphRunner picks -D options too late (majakabiljo)
GIRAPH-737: Giraph Application Master: Move to new and stable YARN API (mislam via ereisman)
Merge remote-tracking branch 'upstream/trunk' into trunk
Merge branch 'trunk' into GIRAPH-ZK

Conflicts:
	giraph-core/src/main/java/org/apache/giraph/bsp/BspService.java
	giraph-core/src/main/java/org/apache/giraph/graph/GraphTaskManager.java
merge last changes for ZooKeeper
Merge branch 'GIRAPH-723' into GIRAPH-KIBBLE