[DISCUSS] Backporting Regionserver Groups (HBASE-6721) to 1.x and 0.98

[Francis Liu]

Hi,
HBASE-6721 is now committed to trunk. It'd be great if it can be backported to 
1.x and 0.98 so that we can use it internally as well as push up features and 
fixes. We have been running an internal version for around 4 years. There's 
seems to be interest (HW, Bloomberg, Salesforce, etc). Also given how modular 
the code is. There's barely any effect in existing code paths. 
Seeding the criteria with Andy's suggestions in jira:
1. Stability - Unit tests and ?2. functional3. Performance - Read/write path 
was not affected. Some small changes related to assignment. 
Thanks,
Francis