Move constants from Drive elsewhere

[onlycs]

Specifically, constants that don't belong there, including but not limited to:

• mass
• MOI
• wheel friction
• speed limits (will be used by, e.g., autos and repulsor)
• physical constants such as length, width, etc

this PR builds off of #16 and #17, just to avoid future merge conflicts and stuff

as a bonus, the new constants are much more well-documented than the old ones.

[stevemurphymsu]

These changes are rejected. Please do not change the location of constants from the advantage kit template.