relax SVN archive

Added two more unit tests.

Fix for the phthalic acid NOE restraint reading system test.

Pseudo-atom creation was not correctly called.

Wrote the create_pseudo_spin() and __linear_ave() functions for pseudo-atom support.

Added two unit tests for the relaxation dispersion code and fixed errors in the corresponding code.

More unit tests will be added soon to help debugging and developing.

Copied 'test_relax_fit.py' to 'test_relax_disp.py'.

This will allow the design of a few unit tests for the relaxation disperison code.

The command used was:
svn cp

Imported the non-existant create_pseudo_spin() function.

Fixes for the arg unit tests of spin.create_pseudo().

Wrote the interface for the spin.create_pseudo() user function.

Wrote 5 arg unit tests for the spin.create_pseudo() user function.

Wrote a unit test for the creation of pseudo-atom spin containers.