fix serialization bug
Merge pull request #83 from huafengw/master

fix serialization bug
Update README.md
Update README.md
fix resource never return back
add default configs
Merge remote-tracking branch 'upstream/master'
add default serialization schema
fix serialization types
Merge pull request #85 from clockfly/master

fix serialization types
Merge pull request #84 from huafengw/master

fix resource never return back
Merge branch 'master' into scheduler

Conflicts:
	streaming/src/main/scala/org/apache/gearpump/streaming/AppMaster.scala
add TaskSet and refactor PriorityScheduler