relax SVN archive

Renamed to isotropic cone functions to the free rotor isotropic cone.

The model name has changed, as the torsion angle was unrestricted in the earlier code.

Simplified and sped up the torsionless pseudo ellipse.

6 functions, and hence 6 numerical integrations, have been deleted as they are repetitive of other
frame order matrix elements.

Ordering of the functions.

Fix for the reduce_and_rot() method, the self arg was missing.

Simplified compile_2nd_matrix_iso_cone() by using rotate_daeg().

The compile_2nd_matrix_*() functions now build the rotation matrix themselves as this is not shared
code.

Abstracted the common code in compile_2nd_matrix_*() into rotate_daeg().

This will significantly simplify the addition of all of the 12 models.

Shifted all of the shared code in the frame order target functions to reduce_and_rot().

This significantly simplifies the code base and removes a large source of bugs.

Partial support for the 12 parametric restriction models of the pseudo-ellipse.

All of the specific frame order code can now support these models. The maths_fns code is still
missing, so not all models are available.

The frame_order.select_model() user fn docstring now describes all 12 parametric restriction models.

Added target function aliases for all 12 parameteric restriction models of the pseudo-ellipse.