Part of PalSelect was used as cache key for palette textures
PrintTexture fix
egl,wgl,xgl: No need for depth/stencil surface
gl: non-functional refactoring
ImGui is now initialized once at startup and shutdown before
terminating. graphics initialization is independent.
Move more imgui stuff into imgui drivers.
switch: set scaling on external screen to 1.4, same as xbox
UI scaling refactoring.
Refactor imgui backend code into imgui drivers for gl, vk, dx9
Generic GraphicsContext interface for gl/vk/dx9 contexts
Simplify graphics api switching code
dx9, gl(sdl): set swap interval based on monitor refresh rate.