Code cleanup 2: Hell's Kitchen

Created by: ComicIronic

Made is_hot and is_sharp object procs, not global procs. Added sharpness vars for objects. Things use these procs OOP now. Made all kitchen knives inherit from utensil/knife. This also fixes an issue with plastic knives, #2863 (closed). Forks now work with all food properly. Fuck oldcode. Made some procs macros, moved a maths proc, shrunk unsorted.dm a little. Removed a redundant get_turf_loc proc that was just get_turf.