Return the Mueller matrix for a system rotator.
- - p is the rotation angle, ranging from 0 to 2*pi,
if not given or set to [] the default value 0 is used.
 - - mode is a string defining the units for the angle:
’radiant’ (default) or ’degree’ (0..360)
 
Argument p can be passed as a scalar or as a matrix or as a
cell array. In the two latter cases, a cell array M of
Mueller matrices of the same size is returned.
References:
-  E. Collett, Field Guide to Polarization,
      SPIE Field Guides vol. FG05, SPIE (2005). ISBN 0-8194-5868-6.
 -  R. A. Chipman, "Polarimetry," chapter 22 in Handbook of Optics II,
      2nd Ed, M. Bass, editor in chief (McGraw-Hill, New York, 1995)
 -  "Mueller calculus",
      last retrieved on Dec 17, 2013.
 
See also: mueller_rotate.