GIRAPH-705: Type converters and giraph-hive cleanup (nitay)
Merge remote-tracking branch 'origin/trunk' into g1
Merge remote-tracking branch 'origin/trunk' into g2
Merge remote-tracking branch 'origin/trunk' into g2
Merge remote-tracking branch 'origin/trunk' into g2
Merge remote-tracking branch 'origin/trunk' into g4
Merge remote-tracking branch 'gh/trunk' into serializer