Basic infrastructure of the UserMonitor, for now counts number of sql queries executed though the SQL and InternalJDBC interfaces.
merge trunk; fix new IS table to be security sensitive too
adjust MonitorService#deregisterUserMonitor processing
adjust MonitorService#deregisterUserMonitor processing again
merge tjoneslo: Add a UserMonitor with IS.SERVER_USERS to show how much work each user is doing.

https://code.launchpad.net/~tjoneslo/akiban-server/add-user-monitor/+merge/161017