VIVO-541 First cut at the developer panel.
Reduce chatter in the log on startup.
VIVO-552 Reduce “memory leak” messages at shutdown.

ThreadLocal stores objects in the threads. If the key type of the ThreadLocal is a class that is specific to the webapp, then that class cannot be unloaded when the app is shutdown, unless the threads themselves are garbage-collected. By using HttpServletRequest as the key to the ThreadLocal, that should be avoided.
Merge branch 'maint-rel-1.6' into develop