BulletSim: experimental movement of physics execution off of heartbeat
thread. Off by default until more testing.

Setting "[BulletSim]UseSeparatePhysicsThread=true" causes the physics
engine to be called on its own thread and the heartbeat thread only
handles the reporting of property updates and collisions. Physics frame
rate is about right but physics execution time goes to zero as accounted
by the heartbeat loop.
New HttpServer_OpenSim.dll with increased limits on number of connections, requests, etc.
BulletSim: fix corner case when rebuilding a compound linkset while
a mesh/hull while a mesh or hull is being rebuilt when its asset
is fetched. This fixes a 'pure virtual function' crash when changing
physical state of complex linksets that include many meshes.
BulletSim: default PhysicsTimeStep to same as the simulator's
heartbeat timestep when running the physics engine on a separate
thread. This reduces the occurance of heartbeats that happen when
there is no physics step which is seen as vehicle jerkyness.
Make locking more uniform
Remove a couple of orphaned lines
Avoid a deadlock where a script can attempt to take a ScriptInstance.m_Scripts lock then a lock on SP.m_attachments whilst SP.MakeRootAgent() attempts to take in the opposite order.

This is because scripts (at least on XEngine) start unsuspended - deceptively the ResumeScripts() calls in various places in the code are actually completely redundant (and useless).
The solution chosen here is to use a copy of the SP attachments and not have the list locked whilst creating the scripts when an avatar enters the region.
This looks to address http://opensimulator.org/mantis/view.php?id=6557
Merge branch 'master' of ssh://opensimulator.org/var/git/opensim
Cleanup
Prevent processing for Npc
Port Avination's inventory send throttling
Merge branch 'master' of melanie@opensimulator.org:/var/git/opensim
Merge branch 'master' of /home/opensim/var/repo/opensim
Committing Avination's Keyframe module. This is not hooked up yet and will do nothing. More commits to follow.
Hook up Keyframe motion to almost everything. Failing to cross a sim border
may yield unexpected results in some cases. No database persistence yet,
Database persistence for keyframes. Contains a Migration.
Strengthen some assumptions.
Merge branch 'master' of ssh://opensimulator.org/var/git/opensim
Fix keyframe motion copyright
Merge branch 'master' of melanie@opensimulator.org:/var/git/opensim