* cmake: Remove zzogl from cmake.
* cmake/build: Remove GLSL_API and EGL_API flags.
Only used in zzogl.
* linux various: Remove zzogl.
* sln: Remove zzogl from old plugins solution.
* zzogl: Remove source files.
* debian: Exclude zzogl from copyright.
* linux various: Remove glsl2h.pl
Used only in zzogl?
* linux various: Remove zzogl code from validate_glsl.sh
* debian: Remove zzogl mentions in create built tarball.
* gitignore: Remove zzogl paths.