relax SVN archive

Spacing fix in an import statement (found using the 2to3 conversion program).

Created the 'NS 2-site' model target function.

This is the model of the numerical solution for the 2-site Bloch-McConnell equations. It originates
as optimization function number 1 from the fitting_main_kex.py script from Mathilde Lescanne, Paul
Schanda, and Dominique Marion (see http://thread.gmane.org/gmane.science.nmr.relax.devel/4138,
https://gna.org/task/?7712#comment2 and https://gna.org/support/download.php?file_id=18262).

This commit follows step 4 of the relaxation dispersion model addition tutorial
(http://thread.gmane.org/gmane.science.nmr.relax.devel/3907).

Updates and fixes for the lib.dispersion.ns_2site module.

The function has been renamed, and the R1 arguments default to 0.0. The flip angle for the
r180x_3d() function has also been removed as the angle has been changed to include the 180 degrees
from the pulse.

Added the 'NS 2-site' R2eff calculating function to the relax library.

This is the model of the numerical solution for the 2-site Bloch-McConnell equations. It originates
as optimization function number 1 from the fitting_main_kex.py script from Mathilde Lescanne, Paul
Schanda, and Dominique Marion (see http://thread.gmane.org/gmane.science.nmr.relax.devel/4138,
https://gna.org/task/?7712#comment2 and https://gna.org/support/download.php?file_id=18262).

This commit follows step 3 of the relaxation dispersion model addition tutorial
(http://thread.gmane.org/gmane.science.nmr.relax.devel/3907).

Added the 'NS 2-site' model to the relax_disp.select_model user function frontend.

This is the model of the numerical solution for the 2-site Bloch-McConnell equations. It originates
as optimization function number 1 from the fitting_main_kex.py script from Mathilde Lescanne, Paul
Schanda, and Dominique Marion (see http://thread.gmane.org/gmane.science.nmr.relax.devel/4138,
https://gna.org/task/?7712#comment2 and https://gna.org/support/download.php?file_id=18262).

This commit follows step 2 of the relaxation dispersion model addition tutorial
(http://thread.gmane.org/gmane.science.nmr.relax.devel/3907).

Added the 'NS 2-site' model to the specific_analyses.relax_disp.variables module.

This is the model of the numerical solution for the 2-site Bloch-McConnell equations. It originates
as optimization function number 1 from the fitting_main_kex.py script from Mathilde Lescanne, Paul
Schanda, and Dominique Marion (see http://thread.gmane.org/gmane.science.nmr.relax.devel/4138,
https://gna.org/task/?7712#comment2 and https://gna.org/support/download.php?file_id=18262).

This commit follows step 1 of the relaxation dispersion model addition tutorial
(http://thread.gmane.org/gmane.science.nmr.relax.devel/3907).

Fix for the Relax_disp.test_hansen_cpmg_data_auto_analysis system test for model name change.

This is for the change from the 'CR72' model to 'CR72 red' model.

Improvements for the write_results() method of the dispersion auto-analysis.

The parameter value and Grace files are now correctly created for all the recent models.

Added support for model nesting in the relaxation dispersion auto-analysis.

This involves copying the parameters from the simpler nested model rather than performing a full
grid search. This is currently used to handle all models with R20A and R20B parameters where a
simpler model with the single R20 parameter is optimised first.

Small speed up for the lib.dispersion.cr72 module for the R20A != R20B case.

Replicated calculations have been minimised.