SDL_gfx dependency and file rename

[David Van Duzer]

Hi all.

I've migrated the SDL_draw code to use SDL_gfx, so if you didn't
already have it installed, you'll need it now. I've also renamed
"slyp" to "slip" where applicable, since we'd been talking about doing
that for awhile.

Happy Tuesday!

dvd

[Bruce Long]

Nice! I'm looking forward to trying it out tonight.

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