If a caller tries to queue a CAPs message to a scene presence that has no event queue (e.g. an NPC), only warn if event queue debugging is greater than zero.

Removes the spurious log warnings if groups are active when NPCs are used.
Adds more regression tests associated with adding messages to the event queue
Merge branch 'justincc-master'
If calls to UserAgentServiceConnector fail then throw an exception. This lets the caller decide whether to discard the error or not.

This is Oren Hurvitz's 0001 patch from http://opensimulator.org/mantis/view.php?id=6956 but I ended up doing some tweaking to resolve patch application issues.
Change warns associated with UserAgentServiceConnector to debugs, as this is not necessarily a problen with the source simulator (e.g. someone else's remote simulator cannot be contacted).

This is Oren Hurvitz's second patch from http://opensimulator.org/mantis/view.php?id=6956 with a small amount of correction
Merge branch 'justincc-master'