WL#1275: SHOW PROCESSLIST Should show tables/locks in use

Affects: Server-7.1   —   Status: Un-Assigned

In order to facilitate diagnosis/analysis of processes that are locked or long 
running, we should expose the following information in SHOW PROCESSLIST (maybe 
SHOW [FULL] PROCESSLIST ???):

* Tables being accessed
* Locks being held

The main entry for lock-display tasks is WL#2333.