some changed on NativeFile, StopWatch and XPregel communicator
Merge remote-tracking branch 'origin/feature/hyperanf' into feature/xpregel
Merge remote-tracking branch 'origin/feature/hyperanf' into feature/xpregel
fix a compilation error on NativeFile
bugfix: the numberOfEdges of Graph object was less than the correct value
Merge branch 'feature/xpregel' into develop