Fixed Mouse Button State Issues

Buttons would cancel each others ButtonState.Pressed  out, as well
rotating the mousewheel would cancel all ButtonState.Pressed
Merge pull request #2198 from davepermen/develop

Fixed Mouse Button State Issues
Added OPENAL definition
Merge pull request #2381 from thefiddler/openal

Added OPENAL definition
We need to copy this list as disposing items in it causes it to be modified.
Merge pull request #2383 from danzel/releaseresources

Fix crash in DisposeAll
Remove unused code from Texture2D.DirectX and do a minor tidy up. Fixes #2306
Tidy up the usings also.
Clamp MediaPlayer volume to [0, 1] range. Fixes #2362
Fix WM_QUIT drain in TestGameBase

According to MSDN, WM_QUIT causes GetMessage to return 0. Checking for
this fixes a hang issue when running the Windows build of MonoGame on
Windows 8.1.
Merge pull request #2388 from thefiddler/win_test_hang

Fix WM_QUIT drain in TestGameBase
Merge pull request #2387 from danzel/fix-2362

Clamp MediaPlayer volume to [0, 1] range
Merge pull request #2386 from danzel/fix-2306

Remove unused code from Texture2D.DirectX and do a minor tidy up
Disable the web platform from being generated by default
Remove ResourceType, nothing referenced it. Fixes #2391
Implement ModelMeshCollection.Enumerator and make the comments proper /// ones.

Fixes #2360
Whitespace and license this file
Make ModelBoneCollection match ModelMeshCollection, with the custom enumerator also.
Whitespace it ModelBoneCollection
Remove brackets to match ModelBoneCollection