defined_ptr: lower case defined_deleter
auto_vec: disallow element assignment. add reset method.
gambatte_sdl: fix print help exit success derp introduced in

44b6913a3ab7f2ecc1eca2abdbf0953d904b34d9

kill failed boolean. use EXIT_FAILURE.
initialize all members.
ringbuf: use array size in fill
gambatte_sdl/audiodata: cleanup. use smart_ptrs for sdl frees.
gambatte_sdl: blitter cleanup