relax SVN archive

Updated all the prompt module unit tests to use the new 'fake_relax' structure.

A file to be imported by all the prompt user test modules for faking the relax instance structure.

File rename.

Created the framework for the unit tests of the diffusion_tensor user functions.

Set up the base class for unit tests of the diffusion_tensor modules.

Removed the run argument from the diffusion_tensor.init() user function.

Removed the selection argument to the generic_fns.selection.exists_mol_res_spin_data() function.

The associated unit test has also been removed.

Big bug fix for the generic_fns.selection.exists_mol_res_spin_data() function.

Wrote 5 unit tests for the generic_fns.selection.exists_mol_res_spin_data() function.

Updated the data model redesign document. All the sequence user functions are implemented.