relax SVN archive

The absolute path to PDB and XYZ 3D structure files is now kept in the relax data store.

This is for both the internal PDB and XYZ reader, and the Scientific Python PDB reader.

Removed some debugging printouts.

The PyMOL and Molmol open_pdb() methods now check for the absolute file path.

If the PDB file cannot be found on the current or relative paths, then the absolute file path is
also checked for and used if the PDB file can be found there. This allows results and save files to
be in non-standard locations.

The structural API base pack_structs() method has been modified to add the absolute file path.

This will be used as a fall back mechanism for loading PDB or XYZ files from old state or results
files if the file cannot be found on the relative path. This is useful for the PyMOL and Molmol
user functions.

Updates for the CaM frame order test data full_analysis.py script.

The domains are now linked to the PDB files for visualisation and the Monte Carlo simulations are
now much less precise to speed up the calculations.

Bug fix for the free-rotor isotropic cone frame order model.

The cone_theta parameter is not an optimised parameter, but a Monte Carlo '*_sim' data structure
needs to be set up for it.

Added some code to allow for results visualisation in the frame order auto-analysis.

This creates the 'cone.pdb' file representation of the motion and a relax script for launching the
visualisation later on.

Created PCS subset files for some of the CaM frame order test data.

Updates to the CaM frame order test data auto-analysis script.

Added a basic class docstring for the frame order auto-analysis.