Add particle test script
Tweak particle test
Give engines names for easier distinction in profiles
Switched to single-threaded architecture
Remove debug statement
Update documentation
Merge separate engines into one

This change allows us to freely arrange all systems and cuts
down on the number of virtual function calls (although in a very
minor way).
Remove debug drawing system

We can do this more effectively now that Bullet and Ogre run in
the same thread.
Remove SharedState templates

We don't need those anymore. Maybe we can bring it back later
for sharing data between threads.
Update EntityManager doc and rename update to processRemovals

The name makes the intention much clearer
Move EntityManager and LuaState into Engine

I don't like making the Engine class even bigger, but those two
just belong there.
Update docs and remove some unused typedefs
Introduce Touchable class

A throwback to SharedData with hasChanges, touch and untouch.
The Lua scripts become a bit more verbose, but the C++ classes
are easier to handle.
Split script initializer

Should help a bit in compilation times
Update documentation
Merge branch 'master' into single_threaded

Conflicts:
	res/dist/scripts/sandbox/particles.lua
	res/dist/scripts/sandbox/player.lua
Merge pull request #38 from Revolutionary-Games/single_threaded

Single threaded