relax SVN archive

Fix for the euler_to_axis_angle_xzx() function.

Created a unit test to check all hard-coded conversion functions for all 12 static axis rotations.

Fix for reverse_euler_zyz() due to the function renaming.

Fixes for all the euler angle to rotation matrix unit tests.

Ordered the euler angle conversion functions.

Renamed all euler_ijk_to_R() functions to euler_to_R_ijk().

Copyright notice update.

Modified the import of euler_zyz_to_R to allow easy switching later on to a different notation.

Clean up of the sub_divide() method.

A docstring has been written, the sub_grid() method has been absorbed into one line of sub_divide()
simplifying the code paths, and comments have been added coving all statements.

Converted a number of methods to private methods.