remove the config of DefaultMobStoreFlusher in test.
Refine the code according to Ram's patch.
Merge branch 'hbase-11339-core' of https://github.com/JingchengDu/hbase into hbase-11339-core
Fix the compile issues in UT.
fix UT.
Fix the issues in HMobStore.
Merge branch 'hbase-11339-core' of https://github.com/JingchengDu/hbase into hbase-11339-core
Fix the issue in HMobStore.
Fix the length issue.
Add category for the testing.
Merge remote-tracking branch 'origin/hbase-11339-core' into hbase-11339-metrics

Conflicts:
	hbase-server/src/main/java/org/apache/hadoop/hbase/mob/DefaultMobStoreFlusher.java
	hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HMobStore.java
	hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/MobStoreScanner.java
	hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ReversedMobStoreScanner.java