relax SVN archive

Small correction for the structure.read_pdb user function description.

Deleted a number of Frame_order.test_distribute* system tests.

These are the four double rotor model tests. The frame_order.distribute user function cannot
operate on these test cases as one of the two torsion angles are set to zero in the tests.

The frame_order.distribute user function now warns when the maximum rotations are reached.

Changed the default max_rotations argument value to 100,000 in the frame_order.distribute user function.

This decrease from one million is so the user function completes in a reasonable amount of time.

The Frame_order.test_auto_analysis system test now sets the results file compression type to bzip2.

Changed the default relax results compression type to bzip2 in the frame order auto-analysis.

This was set to no compression for speeding up some system tests, however the system tests can set
this for themselves.

Speed up of the Frame_order.test_auto_analysis system test.

After the introduction of the frame_order.distribute user function into the auto-analysis, the test
was taking far too long to complete. Now the distribution arguments are set to low values to allow
the test to pass in under a minute.

Improved control of the frame_order.distribute user function in the frame order auto-analysis.

The maximum number of rotations can now be set, and the argument for the total states for the
distribution has been shortened.

Introduced the max_rotations argument into the frame_order.distribute user function.

This is used to prevent the user function from running forever. This happens whenever a cone
opening angle or torsion angle is zero, and hence the random sampling of the rotational space will
never find rotations within the motional distribution.

Implemented the back-end of the frame_order.distribute user function.

This follows the design of the pseudo-Brownian simulation frame_order.simulate user function. The
specific_analyses.frame_order.uf.distribute() function has been created as a modified copy of the
simulate() function of the same module. This simply performs checks and assembles the data, passing
into the new lib.frame_order.simulate.uniform_distribution() function, which itself is a modified
copy of the brownian() function in the same module.