ash/freed   oct 1968   subroutine mnspt
calculation of moon spot coordinates relative to center of moon
modified nov 1972 by r.king to calculate partials w.r.t. lunar
libration parameters

nlibpr=-2 libration and partials determined from eckhardt's series
=-1 libration determined from series, no partials calculated
= 0 libration taken from moon tape, no partials calculated
= 1 libration taken from moon rotation tape, no partials
calculated
= 2 libration and partials taken from moon rotation tape

for nlibpr=1,2, kmr(100) (in /rotdta/) determines type of angles:
=-1 moon rotation angles are euler angles wrt coordinate
system (pep inegration)
= 0 moon rotation angles are cassini libration angles wrt
osculating initial conditions (jpl numerical integration
= 1 moon rotation angles are cassini libration angles wrt
mean elements (eckhardt analytic theory)

the a matrix is no longer calculated in mnspt, but rather in
preces in order to make use of the precession matrix before it
is modified by the ad hoc small rotation angles.  this means that
any adjustment of these angles to account for errors in the
earth's orientation will not affect the orientation of the moon.

determine partial derivatives of spot velocity
with respect to local radius
test if derivs. of spot vel. needed
* caution *  code below not tested