SDL1 support drop

I`m planning to completely remove SDL1 support from codebase.

Windows, Linux builds use SDL2, next android build will also use SDL2 (according to @xyz).

Any objections?

Sure, SDL1 should already be abandoned.

There might be some exotic system which don’t support SDL2, but again, we don’t have active developers for any of them.


About time really. So yeah. Drop it :blush: