Added CMake List for a sound library. AP-180
Updated CMakeList and added CMakeList for Sound library. Added classes sound, sound manager & sound settings.

AP-180
Added error reporting to the sound manager.
Created sub-folders for resources and added textures to corresponding sub-folder.
Added functionality to play music while playing. Changed CMake-files to support fmod.

AP-180
Fix Linux issues.

Also added texture to be drawn when missing resource.
Merge current branches.

Conflicts:
	client/resources/resources.txt
	client/src/CMakeLists.txt
	client/src/Game.cpp
	client/src/ICoreSystem.cpp
	client/src/ICoreSystem.h
	client/src/Platform_Linux/CoreSystemLinux.cpp
	client/src/Platform_Linux/CoreSystemLinux.h
	client/src/Platform_Windows/CoreSystemWindows.cpp
	client/src/Platform_Windows/CoreSystemWindows.h