Mostly cleanup of unused code.
Fixed linespacing to use the font metrics.
Removed unused usings.
Simpler conversion to alpha premultiplied greyscale.
Disabled border padding which is causign artifacts.
Use the font height for unrendered characters.
Dump format on error.
Removed PlatformSetMasterVolume().
XAudio no longer uses MasterVoice.SetVolume.
Added SoundEffectInstance._isXAct.
SoundEffectInstancePool now supports XAct sound instances.
We no longer apply SoundEffect.MasterVolume on XAct sound instances.
Removed volume clamps in XActSound.
XActSound now applies the category volumes.
AudioCategory volume now scales the track volumes.
Fix license for all basic types
Add support for multisampled rendertargets in most OpenGL and OpenGLES platforms
Fix mac build
Disable msaa support for MonoMac (for now)
Fixed GL.RenderbufferStorageMultisample not supported in MonoMac
Add PlatformResolveRenderTargets placeholder to all platforms
Fix Monomac msaa support
Merge branch 'develop' of https://github.com/mono/MonoGame into opengl_msaa

Conflicts:
	MonoGame.Framework/Graphics/RenderTarget2D.OpenGL.cs