This change makes .gitignore viewable in snes9xw.sln. It also updates
the solution to be opened in Visual Studio 2017 by default. This doesn't
prevent it from being opened in VS15 for those not ready to make the
switch.
OpengGL support
full unicode support
x64 build support
shader support (D3D+OGL)
DDraw: vsync, dynamic buffer allocation
restored SPC save option
better window position saving
fixed crash during fullscreen switch