RenderTarget improvements

- Add MSAA support when available (WindowsGL, iOS and Android)
- Add render to cubemap support
- Better Framebuffer object management
Optimized some calculations if the Viewport isn't changed
Some attempts at allowing 16 bit back buffer formats on iOS
Overriden equality operator for Sampler States and Blend States to optimize state changes when two different classes have the same values.
Aggressive inlining for most Vector3 methods
Aggressive inlining of Vector3 methods
Merge branch 'develop' of https://github.com/chusschi/MonoGame into develop
SDL2-CS library.
Merge branch 'develop' of https://github.com/chusschi/MonoGame into develop
Reference and library changed.
* Updated project settings
Merge branch 'develop' of https://github.com/chusschi/MonoGame into develop
Message console Debug
Change fullscreen false always on linux.
Merge branch 'develop' of http://github.com/chusschi/MonoGame into develop
AggressiveInlining not exist in linux
Hotplug pad.
DynamicSound Linux and Mac
Linux files and configuration
Solucionado DynamicSound dejaba de sonar