relax SVN archive

changing the description in the user functions load_spins() and read_xyz().

An example for loading the spins for xyz file format was added in the description of the user function load_spins() and the description of the user function read_xyz() was changed. Both user functions are located in 'prompt/structure.py'.

Debugging the user functions load_xyz() and test_read_xyz_internal2().

The user functions load_xyz() in 'generic_fns/structure/internal.py' and test_read_xyz_internal2() in 'test_suite/system_tests/structure.py' have been changed so that the molecule name can be read properly.

Modified the function for checking the inversion-recovery curve fitting results.

The function was still looking for 'exp_2param_neg' fitting...

Renamed the function for checking the curve fitting results.

Renamed the function for checking the curve fitting results.

The system test script for the inversion-recovery function now uses the good function.

Created a system test script for the inversion-recovery function.

This is based on a copy of the script 'relax_fit_exp_2param_neg.py'.

Created a new test for the 'exp_3param_inv_neg' (inversion-recovery) function.

This is based on a duplication of 'relax_fit.test_curve_fitting_volume_exp_2param_neg()'.

Added '_exp_2param_neg' in the name for the tests currently using the function 'exp_2param_neg'.

This is the first step before making a test for the 'inversion-recovery' function 'exp_3param_inv_neg'.

Modified the tests (and sample script) for the new name of the exponential decay function.

Indeed, the name 'exp' for the exponential decay function has been changed to
'exp_2param_neg'.