TEZ-1288. Create FastTezSerialization as an optional feature (rajesh)
TEZ-1319. TEZ-1321. Remove methods annotated as @Private from TezClient
and DAGClient. (sseth)
TEZ-1300. Change default tez classpath to not include hadoop jars from
the cluster. (sseth)
TEZ-1257. Error on empty partition when using OnFileUnorderedKVOutput and ShuffledMergedInput