[Feature Request] Screen Rotation

[noswanson1982]

As of right now, there is no way to rotate the screens in the MelonDS core of Retroarch. Sure, I can orient the screens the correct way, but there is no way to rotate the content within the screens to match. MelonDS DS has this functionality (just has problems with the microphone) while this has no way of rotating the screens (but has working blow features with the microphone). This is really an issue for games like Mario & Luigi: Bowser's Inside Story (which requires both being able to rotate the DS, and have working microphone support). I feel we are really close to having a core that can do both.