Hotwiring [WIP]

Cars may spawn without keys in ignition, requiring some kind of bypass in order to use them. Similar to #421, except I won't be adding/spawning keys. Assumed that vanilla behaviour implies keys are already in the ignition.
Critical failure will mean that an alarm starts, alarms will last until batteries are flat, then will not come back on.
Balance thoughts: should vehicles that need to be hotwired be in otherwise working condition?  How often should vehicles be without keys?

- [x] Prevent control usage when vehicle has no keys.
- [x] Allow screwdriver to be used to attempt to hotwire, unlocking controls.
- [x] Add chance of failure to screwdriver, depending on mechanics.
- [x] On failure, alarm triggers.
- [x] Only sound alarm if batteries are charged.
- [x] Light failure will unlock controls, but trigger alarm.
- [x] Save additional variables in json
- [x] Add alarm part
- [x] Make alarm part not easily removable
- [ ] possibility of damaging controls rather than triggering alarm
- [ ] Make it so that there is not a 100% chance of a vehicle being locked
- [x] Make it likely that a locked car will be in better condition
Thanks for restyling, I was just looking at this and being annoyed, but I wasn't modifying it, so random restyling and resulting conflicts would be bad :D