Expose glam as our vector math library / Vector type #20
Description
Bevy uses glam and so we should to. I'm not sure what the right balance is here. Should we have an API object for each vector type? That seems weird. These can also tend to be relatively hot pieces of code. In some languages, they may want to use their own vector math libraries, which is something we'll want to consider as well, although glam is pretty good overall and has good support for SIMD.