Trying out a major refactor
Refactor working for fixed attitude cartesian
Added 'derivp' flag to CARTSTATE

Checks if state class object is a derivative, so that derivative slots
aren't calculated if it's bound
Bunch of changes. Split original in to multiple files. Added time to new state.
Further progress
Added export routines for plotting 3D cartesian data
Reorganization of original files.

Split examples. Moved around some things.
Fixed units in EOM2 examples to use km/kg/s, new table propagation that splits integration along RS-TABLE
examples.lisp now all work with propagation across RS-TABLE slot
adding basis & normal functions