Added music class
Added Music loader
CherryPicked commit "Reworked ResourceLoader"

Conflicts:
	src/Nazara/Utility/Loaders/MD2/Loader.cpp
Fixed some leaks
Fixed music looping
Gui branch

backup branch
Added Renderer::GetDepthFunc
Fixed Color::operator[+|*](=)
Deferred Shading update

-Deferred Shading now use a dynamics pass system
-Forward Shading is now capable of rendering more than three lights
(Multipass)
Modified comments
Fixed bloom pass
Modified DynLib/PluginManager interface
Modified PluginInterface internal

-No more warning when adding a non-existing directory
Added move constructor/operator to DynLib
Audio update

OpenAL is now loaded dynamically
Added (back) Audio::[Get|Set]ListenerRotation
Some changes in DynLib internals
Fixed DynLib::Load not emitting error on failure
Fixed instancing not enabling in some conditions
Merge remote-tracking branch 'origin/Audio-update'

Conflicts:
	include/Nazara/Core/ResourceLoader.hpp
	include/Nazara/Core/ResourceLoader.inl
	src/Nazara/Audio/Loaders/sndfile/Loader.cpp
	src/Nazara/Audio/Sound.cpp
	src/Nazara/Utility/Loaders/MD2/Loader.cpp
	src/Nazara/Utility/Loaders/MD5Anim/Loader.cpp
	src/Nazara/Utility/Loaders/MD5Mesh/Loader.cpp
	src/Nazara/Utility/Loaders/PCX/Loader.cpp
	src/Nazara/Utility/Loaders/STB/Loader.cpp
Fixed last commit

I hope one day i will merge without any error !