Usage:
<annihilator1 X ann_X
computes the annihilator by calling "quotient"
Parameters:
X = a module
Output values:
ann_X = its annihilator, as an ideal with standard
basis.
This script essentially computes the intersection
of the annihilators of all the generators of X.
A different method -- sometimes faster, sometimes
slower -- is used by "<annihilator2