Add lua_getmainthread function to return main thread.
Add coroutine.start and coroutine.sleep in Lua.
Add Lua coroutine sample.
Add new line at end of file.
Add Sprite2D and Drawable2D.
Add SpriteSheet2D and StaticSprite2D.
Add ParticleEmitter2D.
Add Urho2DSprite sample.
Add script binding for Urho2D.
Add asset for Urho2D.
Add Lua Urho2D Sprite sample.
Add AngelScript api.
Travis CI: API documentation update at 2014-02-27 16:14:04 UTC.
[ci package]
Merge remote-tracking branch 'upstream/master'

Conflicts:
	Source/CMake/Modules/FindUrho3D.cmake
	Source/Engine/CMakeLists.txt
	Source/Engine/LuaScript/CMakeLists.txt
	Source/Engine/LuaScript/LuaScript.cpp
	Source/Engine/LuaScript/LuaScript.h
	Source/Engine/LuaScript/ToluaUtils.cpp
	Source/Engine/LuaScript/pkgs/LuaScriptLuaAPI.pkg
	Source/Samples/CMakeLists.txt
	Source/ThirdParty/Lua/src/lapi.c
	Source/ThirdParty/Lua/src/lua.h
	Source/ThirdParty/LuaJIT/src/lj_api.c
	Source/ThirdParty/LuaJIT/src/lua.h