Refactor ReferenceFrame to be a class, not an enum
Add Position method to Vessel, CelestialBody and Node
Make reference frame parameter optional
Add transform methods for conversion of vectors between reference frames
Use default reference frame in autopilot test
Add tests for SpaceCenter.TransformPosition
Add transform velocity tests
Compute reference frame velocity for Sun reference frame (which doesn't have an orbit object)
Refactor reference frame creation
Clean up
Fix KRPCMethod attribute
Add CelestialBody.RotationalSpeed
Clean up and implement more of ReferenceFrame functionality, add tests
Refactor reference frame constructors
Implement reference frame position
Add additional orbit tests
Improve error messages
Add comments
Implement QuaternionD.Inverse using double precision floating point
Add double precision stubs for missing geometry routines