Use bitflags instead of home-rolled constants for flags

Created by: huntergoldstein

Problem

• Rules and bit fiddling can be difficult to remember for bitflags; the more someone has to think through and remember how this all works the more likely they are to make a mistake
• It is harder to debug which flags are set when: most methods either are prone to human error or are tedious

Solution

We could make use of the bitflags crate which should be as efficient as just using constants but increases quality of life (see above).