Normalize rotation matrices used to apply diffuse symmetry in diffBragg
o Required to make a number of them proper rotation matrices
o Also add some comments and change matrix name to clarify what's
going on when the principal axes of the diffuse model are rotated
Normalize rotation matrices used to apply diffuse symmetry in diffBragg o Required to make a number of them proper rotation matrices o Also add some comments and change matrix name to clarify what's going on when the principal axes of the diffuse model are rotated