Replaced \ulcorner...\urcorner with \Gn{...}

Also replaced \square_... \Gn{...} with \Proves[...]{...}
stripped comments
Removed Boxworld.
Removed loebstacle-agi-paper.tex
Removed Goedel numbers after turnstyles
Renamed \Gn to \Quote
Tweaked quoting explanation.

Probably still needs work, though.