relax SVN archive

The structure.find_pivot user function now accepts the func_tol and box_limit arguments.

This allows the function tolerance for the simplex optimisation to be specified, as well as the
size of the box to constrain the pivot to be within.

The structure.find_pivot user function now uses the logarithmic barrier function.

This is for constrained optimisation and requires the newest minfx code. The pivot position is
constrained within a box of +/- 1000 Angstroms from zero. This is needed for when the solution is
an infinite line - i.e. a rotation axis and not a pivot point. Previously the simplex optimisation
would head toward + or - infinity. But now with a logarithmic barrier, the simplex algorithm can
stabilise and find a point on the axis very quickly, long before reaching the edges of the box.

Import fix for the shift of the pivot finder target function.

Added a document detailing the possible future layout of relax's packages.

Added a sentence to the README file about the sample_scripts directory.

Shifted the ensemble pivot finding target function into the maths_fns package.

The structure.find_pivot user function now accepts the func_tol argument.

This is used to terminate the simplex optimisation when this function tolerance value is reached.

Created the Structure.test_web_of_motion_13 system test.

This was just to be sure that the models argument was correctly handled by the structure.web_of_motion
user function.

Fixes for the Structure.test_web_of_motion_12 system test.

The PDB output was not compared to the correct results.

Implemented the models argument for the structure.web_of_motion user function.

This was previously not being used and was caught by the Structure.test_web_of_motion_12 system
test.