Minor refactor.

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1560236 13f79535-47bb-0310-9956-ffa450edef68
HAMA-857: Graph Combiners is wrongly implemented (edwardyoon)

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1560570 13f79535-47bb-0310-9956-ffa450edef68
Revert r1556691

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1560605 13f79535-47bb-0310-9956-ffa450edef68
Remove skipiterator feature

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1560606 13f79535-47bb-0310-9956-ffa450edef68
Fix unit test of PageRank.

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1560607 13f79535-47bb-0310-9956-ffa450edef68
HAMA-838: Refactor aggregator.

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1560672 13f79535-47bb-0310-9956-ffa450edef68
Merge branch 'trunk' of github.com:yxjiang/hama into trunk
HAMA-860

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1561622 13f79535-47bb-0310-9956-ffa450edef68
Update my info

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1562021 13f79535-47bb-0310-9956-ffa450edef68
HAMA-859: Leverage commons cli2 to parse the input argument for NeuralNetwork Example

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1562074 13f79535-47bb-0310-9956-ffa450edef68
Merge branch 'trunk' of https://github.com/apache/hama into trunk