Add a few missing equality operators to Input structs.

Add equality operators and Object.Equals() overrides to the
GamePadButtons, GamePadDPad, GamePadThumbSticks, and GamePadTriggers
structs in the MonoGame.Framework.Input namespace.
Make SoundEffect.Play not throw an exception on iOS if it fails to play, return false instead as we are meant to.
Implement TryPlay on other platforms.
Fix playing multiple music tracks, previously when the first one finished we'd play the second which would reset the queue.
Make SpriteBatch.DrawString() an atomic operation.

Basically, if SpriteSortMode is "Immediate", only flush after
an entire SpriteFont.DrawInto() call, not after each character.

Reduces number of draw calls by ~90% in some text-heavy scenes,
without (as far as I can tell) diverging from the Xna spec. Doesn't
seem to break anything in the MonoGame tests, either!
Added ScissorRectangle reset after render target change
Merge pull request #2093 from kfazi/scissor_issue

Added ScissorRectangle reset after render target change
Merge pull request #2087 from sulix/spritefont-fix

Make SpriteBatch.DrawString() an atomic operation.
Update Libs to SharpDX 2.5.
Merge pull request #2058 from danzel/fix-mediaplayer-queue

Fix playing multiple music tracks from a collection
Merge pull request #2056 from danzel/fix-ios-audio-crash

Fix SoundEffect.Play return value and iOS/Mac crash
Merge pull request #2046 from PrecisionMojo/_pm/add-missing-input-equality

Add a few missing equality operators to Input structs.
Merge pull request #2096 from KonajuGames/sharpdx-2.5

Update Libs to SharpDX 2.5.
changes to support clean exit of MonoGame on macs, and default to fullscreen on 2nd display if present
support xbox 360 controller on OS X
disable gl extensions dump to console
subproject commit

was 304135631ce063580f1c2f9e94b43761ee9d49b0
Merge branch 'develop' of github.com:troydawson/MonoGame into develop