relax SVN archive

Modified the check_return_conversion() method to print out more information for debugging.

Wrote all the test_R_to_euler_ijk() unit tests to cover all Euler angle conventions.

Converted all the R_to_euler_zyz() unit tests into one.

This will simplify the setup of the unit tests for the other Euler angle conventions.

Added all the 12 Euler angle notations to the rotation matrix module.

The methods added include:
axis_angle_to_euler_ijk(),
euler_ijk_to_axis_angle(),
euler_ijk_to_R(),
R_to_euler_ijk(),
reverse_euler_ijk().

Bug fix for the calc_rotation() function.

The axis permutation for | Azz | >= | Ayy | >= | Axx | is now correctly performed.

Bug fixes for the calculation of the anisotropic and rhombic alignment tensor parameters.

Added geometric parameters to the align_tensor.display() print out.

Added the rhombicity R and asymmetry eta parameters to the alignment tensor object.

Renamed the rotation matrix back to 'rotation'.

This is because R will be used as the 'R' alignment tensor parameter.

Added the anisotropic Aa and rhombic Ar parameters to the alignment tensor object.