Complete rewrite of reference frames.

[dahlend]

This is a fundamental rewrite of how rust backend handles frame of references.

There is no longer an Enum which defines possible frames, frame information is now embedded in the type information. This helps with a few things:

• Less data to carry around (not a lot, but everything helps)
• Some conversions used to be fallible, now all frame conversions are infallible.
• NonInertialFrames are now their own Type, and support for them has been restricted to where it belongs.
• Vectors now exist in the Rust similar to the python, these Vectors carry Frame type information.

• Current testing shows a general slight speed improvements, I would imaging primarily coming from making everything infallible.

[dahlend]

I want to revisit this at a later time, this is a really nice structural change, but a large one.