Librarification, OpenGL requirement, wayland support, manpages.

Slop was remade to be cleaner, faster, and easier to use.

It's options parser was re-written so many flags/options now function differently, don't exist, or were renamed.

Now slop requires basic OpenGL stuff to compile, but will easily function without it. If it fails to launch an OpenGL context, it'll use the XShape extension instead.