relax SVN archive

The user function 'relax_fit.curve_type' has been renamed to 'relax_fit.select_model' to bring it
into line with the model-free functions.

Bug fix: The model-free prompt function now prints the 'res_num' argument.

The following functions have been added to the file 'specific_fns/relax_fit.py' in preparation:

self.assemble_param_vector()
self.data_names()
self.grid_search_setup()
self.linear_constraints()
self.minimise()
self.model_setup()

A few other fixes have been added to 'specific_fns/relax_fit.py'.

The 'data_init' function of 'specific_fns/model_free.py' has been simplified a little.

The relax_fit minimise function has been added to 'specific_fns/specific_setup.py'.