relax SVN archive

Set notation fix: Changed the square and round brackets to curly brackets and replaced ':' with '='.

Fixed a bug in the model-free sample script in the spheroid diffusion tensor function.

Fixed some grammer in the intro chapter of the manual (fixed vice versa).

Creation of a framework for a relax test suite to check for regressions and new bugs.

A number of initial tests have also been added.

Rolling back the bug fix to #5501 committed in r2389 which is causing breakages throughout the
program.

Bug fix:

The grid search for the tm parameter (either global or local) was only from 6 to 12 ns. This has
been changed to 1 to 12 ns.

Some further fixes to the auto_select fuctionallity. Adds support for
other run types and fixes problem loading relax_fit data

Creating unstable branch to work on fix to bug 5501

The addition of Py_DECREF() calls to try to prevent the memory leak present in the relaxation
curve-fitting C modules.

Reverted the behaviour of gcc compilation so that the -fPIC option is used.