Merge pull request #2790 from flyingdevelopmentstudio/FixTexture2DSaveAs

Fix Texture2D SaveAs to work on WindowsGL
Moved all the graphics and logos into its own repo.

https://github.com/Mono-Game/MonoGame.Logo
Added new icons.
Fixed Android splash and icon.
Fixed VS template preview images.
Fixed template ico files.
Fixed some splash screens.
Fixed OUYA icon.
Fixed some VS template icons.
Added platform specific VS template icons.
Fixed MonoDevelop icons.
MonoDevelop template images.
New installer art.
Remove old embedded icon.
We now get the form icon from the EXE resources.
Tweaked offset of logo.
Merge pull request #2791 from SickheadGames/logo

New MonoGame Logo
Update README.md

Removed broken image reference.
Merge branch 'develop' of https://github.com/mono/MonoGame into InfiniteFlight
Remove unecessary glFlush call