relax SVN archive

Added checks for the n_state_model.cone_pdb user fn in the N_state_model.test_5_state_xz system test.

Created the Frame_order.test_cam_free_rotor system test for the CaM synthetic data.

Created a script for animating the CaM free rotor frame order model test data in PyMOL.

Added the frame order free rotor optimisation script and its results.

The structure.read_pdb user function can now handle bzip2 or gzip compressed PDB files.

Calculated the pure RDC tensors for the free rotor CaM frame order model.

Back calculated the RDC and PCS test data from the CaM free rotor frame order model.

The structure.write_pdb user function can now create compressed (bzip2 or gzip) PDB files.

The structure.rotate user function can now operate in individual structural models.

The model keyword argument has been added to allow this.

Created a PDB distribution of CaM orientations for the free rotor frame order model.

This is a uniform set of rotations about the pivot-CoM axis.