Review Board 1.7.22

HBase-4348 Add metrics for regions in transition

Review Request #4402 - Created March 19, 2012 and updated

Himanshu Vashishtha
This patch is for adding Region in transition metrics to the HMaster metrics system. It also adds these metrics in the master ui, in the Region in transition section. I have attached the proposed new format in the jira 4348.
Ran on a 5 node cluster and kill region servers randomly to observe the changes in the RIT metrics as emitted out by the Master's mxbean;

mvn test passes without any failure.
Review request changed
Updated (April 4, 2012, 9:47 p.m.)
Changed the name of the property for defining the threshold time limit to show the Region in transitions in UI; ans other nits from Ted.
Ship it!
Posted (April 5, 2012, 12:41 a.m.)
I'm happy with this.  Ted do you have comments?  If no, I'll commit in about 24 hours.
I like this name.