relax SVN archive

Allowed the spin_num arg of spin.create() to be None.

This is useful for polymers where the name is important rather than number.

Fixed the check for None in molecule.name().

Fix for the test_name_argfail_mol_id() unit test.

The mol_id can be None, i.e. for naming unnamed molecules.

Fix for the calc_tensor_diag() function.

The algorithm for finding Ayy was broken.

The diagonalised alignment tensor is now being created (and is being done correctly).

The EntityCompIndex saveframe is now being created.

The translate function now converts all list data elements into strings.

Switched from a RelaxError to 'non-polymer' for anything that isn't a polymer.

A RelaxWarning is thrown so the user can check for FUBAR entries.

The residue numbers are being stored in self now.

The molecule type is now determined.