scheduler patch
Merge branch 'SKT-2014-07-18' of https://github.com/gruter/incubator-tajo_g into SKT-2014-07-18-scheduler
Conflicts:
	tajo-client/src/main/java/org/apache/tajo/client/TajoClient.java
debugging
changed tail limitation
Merge branch 'SKT-2014-07-18-scheduler' of https://github.com/gruter/incubator-tajo_g into skt-scheduler

Conflicts:
	tajo-core/src/main/java/org/apache/tajo/master/DefaultTaskScheduler.java
	tajo-core/src/main/java/org/apache/tajo/worker/TajoResourceAllocator.java
implemented fair scheduler