[All platforms]: Window.IsBorderless feature

new feature
[WinDX]: IsMouseVisible + IsBorderless

code for IsMouseVisible and IsBorderless properties
[WinDX]: Clean up

Now hides the cursor by default (XNA does this).
[WinGL/Linux]: Window.Borderless feature

new feature
[All platforms]: GameWindow comment rename
Fix rendertarget rendering (OpenGL)
[WinGL]: Fix for IsMouseVisible

This fixes IsMouseVisible on windows platforms, It is the only solution I could think of as the current Linux implementation works fine. This works just like XNA.
[WinGL]: Removed unused IsMouseVisible code

Linux now only uses that method
[WinGL/Linux]: Default to hidden cursor.

By default the cursor is hidden in XNA.
[WinGL/Linux]: Default to hidden cursor 2

Noticed that OnIsMouseVisibleChanged wont be called during startup when it needs to be.
Moved argument checking before platform code.
Added more correct exception for iOS.
Update README.md

Updated build server badge.
Merge pull request #1423 from SickheadGames/GetDataWarn

Texture2D.GetData() Improvements
Added OUYA solution.
Merge pull request #1403 from flyingdevelopmentstudio/develop

Fix rendertarget rendering (OpenGL)
Merge pull request #1389 from xanather/develop3d

IsMouseVisible + Window.IsBorderless
Merge pull request #1432 from SickheadGames/ouyasln

Added OUYA solution
Added checks to build script to detect MacOS and to
build Mac and iOS if the correct tools are installed
Fixed a few issues with the MacOS detection