This user function will be similar to frame_order.simulate. However instead of creating a PDB file
with models from a pseudo-Brownian simulation, the frame_order.distribute user function will
generate a PDB file of models forming a uniform distribution of structures covering the full frame
order motional space.
The new system tests are:
Frame_order.test_distribute_double_rotor_mode1_xz_plane_tilt
Frame_order.test_distribute_double_rotor_mode1_z_axis
Frame_order.test_distribute_double_rotor_mode2_xz_plane_tilt
Frame_order.test_distribute_double_rotor_mode2_z_axis
Frame_order.test_distribute_free_rotor_z_axis
Frame_order.test_distribute_iso_cone_z_axis
Frame_order.test_distribute_iso_cone_xz_plane_tilt
Frame_order.test_distribute_iso_cone_torsionless_z_axis
Frame_order.test_distribute_pseudo_ellipse_xz_plane_tilt
Frame_order.test_distribute_pseudo_ellipse_z_axis
Frame_order.test_distribute_pseudo_ellipse_free_rotor_z_axis
Frame_order.test_distribute_pseudo_ellipse_torsionless_z_axis
Frame_order.test_distribute_rotor_z_axis
These are aliases for the equivalent Frame_order.test_simulate_* system tests which have had the
'type' keyword argument added, defaulting to 'sim', which allows to switch between the
frame_order.simulate and frame_order.distribute user functions. The concept behind these system
tests are the same for both user functions, so the code is shared.
