relax SVN archive

The structure.load_spin user function window spin ID field is now a combo box defaulting to '@N'.

This is in the wizard base page spin_id_element() method and the choices are currently '@N' and
'@C', but any value can be used.

Argument change_all for deselecting residues in the d'Auvergne protocol has to be boolean.

The spin viewer now updates and shows nothing if all data has been deleted from relax.

All data pipes associated with an analysis are deleted when that analysis is closed.

The spin count in the auto NOE analysis page is now updated when a user function completes.

Created the prune_mol(), prune_res(), and prune_spin() Mol_res_spin_tree methods to prune the tree.

Created 3 new fns, get_molecule_ids(), get_residue_ids(), and get_spin_ids().

These return lists of molecule, residue, and spin ID strings.

The residues and spins in Mol_res_spin_tree are now only created if they are new.

Molecules are now handled differently in Mol_res_spin_tree if the already exist or not.

New molecules are added to the tree while old ones are left alone.

Split up the Mol_res_spin_tree.update() method into separate methods for molecule, residues, and spins.