relax SVN archive

Added the atom_id arg to the new structure.displacement user function front end.

This will be used to restrict the calculation to subsets of all atoms.

Created the front end for the new structure.displacement user function.

This is used to calculate the rotational and translational displacement between two models.

Extended the N-state model analysis to allow a separate paramagnetic centre per state.

Bug fix for the pymol.cone_pdb user function for when there is no average domain position.

This is necessary for the old 2-domain N-state model analysis type.

Bug fixes for the n_state_model.cone_pdb user function.

The code was old and not functional any more.

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.