Removed old "Libs" submodule.
Added new dependencies submodule.
Updated all references from ThirdParty/Libs to ThirdParty/Dependencies.
Fixed windows style slashes.
Fixed submodule to use HTTPS URL.
Merge pull request #185 from extrahotchilipowder/monogame-sdl2

[FNA] #147 tabbing and cleanup of ./BoundingBox to Curve, plus undo a for to foreach change in Graphics/SpriteBatcher
Tedious style things
Clean up ContainmentType, CurveContinuity
&& 1
Merge pull request #2318 from mono/Dependencies

Dependencies
Updating to latest dependencies with CppSharp.
Remove unneeded 'this' keywords
Merge pull request #2320 from SickheadGames/cppsharp

Updating Dependencies For CppSharp
Remove GraphicsExtensions, move methods where necessary
Implementing GetValueVector2Array

Replicating implementation on GetValueSingleArray.
Merge pull request #2321 from termoventilador/develop

Implementing GetValueVector2Array
Fix loading TextureCubes in background threads on OpenGL platforms.

Adds the same calls to the UI thread present in Texture2D.OpenGL.cs to TextureCube.OpenGL.cs.
Merge back from develop, reject submodule changes
Merge pull request #2323 from jbeshir/fix-texturecube-background-thread

Fix loading TextureCubes in background threads on OpenGL platforms.
Pull some safe code out of a try block