AntiSpam refactor!

Adds SLURLs to antispam notifications
Reduces weight of antispam to either global queue, multiple queues, or none
Renames variables to make more sense
Repositions code, cleans up code, uses modern C++, etc
This fixes a bit of a leak or two, especially with antispam turned off!
Also fixes the endless leak of queue expansion by cleaning up while idle
When changing between global and individual queues, they're now purged.
Also made some improvements to previous commit, woops.
Also fix wrong logic for is_linden and chat source type for objects

indra/newview/llagent.cpp

@@ -908,7 +908,7 @@ void LLAgent::setRegion(LLViewerRegion *regionp)
 		if (mRegionp)
 		{
 			// NaCl - Antispam Registry
-			NACLAntiSpamRegistry::purgeAllQueues();
+			if (auto antispam = NACLAntiSpamRegistry::getIfExists()) antispam->resetQueues();
 			// NaCl End
 
 			// We've changed regions, we're now going to change our agent coordinate frame.