Apply rigid-body rotation around the center of mass (COM) so that the current configuration
best matches that stored in <tt>SR1</tt>.

<p>
Requires <tt>input = 1</tt> or <tt>2</tt> or <tt>3</tt> to be set before calling this command,
to specify whether rotation is around x or y or z axis.  Currently only rotation around z axis 
has been implemented.

<p>
Also see <tt>setconfig1</tt>, <tt>translate_com</tt>.
