Fixes one-way trait clash re: lightweight/substance tolerance.
Show a dynamic menu when examining vehicle parts.
Integrate "Use hotplate" using common code for both kitchen and chemlab.
Only show "fill a container" and "have a drink" if the vehicle has water in the container.
Removed unneeded else ifs, because the previous if is always returning.
Only show menu entries if the vehicle has enough battery.
If there is only one option, don't ask the user.
Strengthens RAINPROOF

Addresses #3413, by halving the chance for water to get inside rainproof
gear and having wielded umbrellas force any drenching to the legs and
feet.
Provide assigned keyboard shortcuts for the menu entries.
Merge fixes to trait interactions and enhanced rain protection.
Merge dynamic vehicle interaction menu.
Merge branch 'master' of https://github.com/CleverRaven/Cataclysm-DDA into tasty-fishies!