relax SVN archive

Modified the cone_edge() function to add atoms for the latitude lines as well.

Added theta_max() methods to all the isotropic cone classes.

This is for determining theta from the phi polar angle.

Added the cones module to the __all__ package list.

The back-calculation of Ri data via model-free and diffusion tensors has been added to the system tests.

Updated the generate_ri.py sample script to work with the current relax code base.

This code was old and broken. A copyright notice has been added.

Fix for the back_calc() function - if the back-calculation returns no value, the spin is skipped.

Fix for the back_calc_ri() API method.

Spins are now skipped if no bond vector information is present (for the spheroids and ellipsoids).

Comment fixes - relax handles spins, not residues now.

Fixes for the back_calc() method.

The find_index() function was already defined (so renamed to find_ri_index()), and the analysis
specific API back_calc_ri() method was incorrectly called.

The back_calc_ri() analysis specific API method has been activated.