relax SVN archive

Created an empty module to dump RDC related computational functions into.

Fix for the N_state_opt class set up for the tensor optimisation.

Changed the N_state_opt functions to be model dependent.

The func_rdcs() method is now func_population(), and the func_tensors() method is now
func_2domain().

Modified the N_state_opt class to handle both alignment tensor and RDC optimisation.

The N_state_opt class now accepts the model, rdcs, and xh_vect arguments.

Fix for minimise_setup_rdcs(). The spin id is now generated for the warning.

Merged revisions 6879 via svnmerge from
svn+ssh://bugman@.../svn/relax/1.3

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r6879 | bugman | 2008-07-09 15:04:27 +0200 (Wed, 09 Jul 2008) | 3 lines

Modified the spin_loop() to return the spin identification string if asked.
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Modified minimise_setup_rdcs() to throw a warning if RDCs exist but XH bond vectors are missing.

Modified the spin_loop() to return the spin identification string if asked.

Created the minimise_setup_rdcs() method.