game: Fix a bug in ralloc usage

I added a bug in

  commit 8d49feb35acfdf578644897c93949fbe71b5752a
  subject: "game: Use ralloc for all memory allocation"
game: Define types for vbuffer, ibuffer, and varray

Type safety for ftw. Define the types below and use them to replace
usage of raw uint32_t.

    game_varray_t
    game_vbuffer_t
    game_ibuffer_t
game: Implement funcs game_prog_from_filenames/from_shaders

Also add funcs game_prog_is_linked and game_prog_get_info_log.
game: Add func xrzalloc
wip
game: Define game_shader_ralloc_dtor

The destructor really deletes the shader.
game: Add mem_ctx params to shader constructors
game: Add destructor for game_prog_t

The program was never really deleted.
game: Add funcs game_shader_is_compiled/get_info_log

And refactor the constructors to use them.