implemented vehicle::face_vec
give a chance to recover in a skid, depenging on

chance, and move & face vectors being somewhat aligned.
moving skid recovery

from inside map::vehproceed
to vehicle::possibly_recover_from_skid
make vehicle control regaining make more sense

by eating the sideways velocity.
also fixing rl_vec dot products, broken from from last commit's fix
Updated rollmat description to make it more descriptive.
Merge branch 'master' of https://github.com/TheDarklingWolf/Cataclysm-DDA
Added a 3in string to 50 thread recipe. All rope disassembly is handled via the disassembly key.
Cots no longer prompt a warning
Make lockpicking and forcing doors take time whether it works or not.
Add message indicating failure to pick a lock.
Refactor lockpicking code to not repeat itself so much.
Add varable strength requirements for moving different furniture types.
Make the rest of the esged weapons ueable as cutting tools.
Refactor crowbar code to repeat itself less.
Factor mechancs skill in to lockpicking and door forcing.
Make picking a lock unlock the door instead of also opening it.
Give lockpicking and prying open alarmed doors have a chance of setting off alarms.
Replace the city mongroup with static spawns of zombies scattered about.
Make spawns dencer at the center of towns.
Centralize the monster despawn logic in a single method.