Fixed mouse scroll wheel on WinDX desktop.
FindImporterByExtension() is no longer case sensitive.
Fixed case where a disposed texture is still in the TextureCollection.
XAudio2 creation can fail.
Fix to using Any() instead of Count().
Fixing SoundEffect.Play so that it sends the default pitch in Xna, 0.0f.  The old value of 1, caused extremely high pitched sounds in Xna on iOS and SoundEffectInstance already uses 0 as the default.
Merge pull request #1493 from nickdarnell/develop

Fixing SoundEffect.Play so that it sends the default pitch in Xna, 0.0f....
Merge pull request #1466 from SickheadGames/miscfix

Misc Fixes