Merge branch 'luasynced_split' into develop

Conflicts:
	rts/Lua/LuaContextData.h
	rts/Lua/LuaEventBatch.h
	rts/Lua/LuaHandle.cpp
	rts/Lua/LuaHandle.h
	rts/Lua/LuaHandleSynced.cpp
	rts/Lua/LuaRules.cpp
	rts/Lua/LuaUI.cpp
	rts/Lua/LuaUtils.h
	rts/Sim/Features/Feature.cpp
	rts/Sim/Misc/ModInfo.cpp
	rts/Sim/Projectiles/Unsynced/ShieldProjectile.cpp
	rts/Sim/Units/Scripts/LuaUnitScript.cpp
	rts/Sim/Units/Unit.cpp
	rts/System/EventHandler.h
	rts/System/GlobalConfig.cpp
	rts/System/GlobalConfig.h
	rts/System/Platform/Linux/myX11.cpp
	rts/lib/lua/include/LuaUser.cpp
	rts/lib/lua/src/lmathlib.cpp
check for NaNs & Infs in LuaParser
don't use c++ static global in LuaUtils::LowerKeys
makes such things make it unthreadable
forgot those in the merge
Merge branch 'develop' of github.com:spring/spring into develop
fix #4262: workaround m$'s spaces bug by using shortpaths