Revision 1001911

HBASE-3039 Stuck in regionsInTransition because rebalance came in at same time as a split

M src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java
  Add region name to warning log message (w/o it message is no good).
M src/main/java/org/apache/hadoop/hbase/master/ServerManager.java
  Add src of split message else need to deduce where it came from by looking
  elsewhere.
M src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java
  Updated log messages to include region and where appropritate source
  server name; debug hard w/o
  Changed regionOnline and regionOffline to check for unexpected
  states and log warnings rather than proceed regardless.
  Added in fix for concurrent balance+split; split message now
  updates regionsintransition where previous it did not.
  Remove checkRegion method.  Its a reimplementation of
  what regionOnline and regionOffline do only less comprehensive
  regards what gets updated (this.regions + this.servers rather
  than this.regions, this.servers and regionsInTransition)
  That they were less comprehensive is root of this bug.
M src/main/java/org/apache/hadoop/hbase/master/HMaster.java
  Make the message about why we are not running balancer richer
  (print out how many reigons in transition and more of the
  regionsintrnasition list).
M src/main/java/org/apache/hadoop/hbase/executor/RegionTransitionData.java
  Javadoc and minor formatting.