This method returns a list of all possible ways to realize N as a minor of M. The output is a list of pairs (S, T) of subsets of the ground set of M such that minor(M, S, T) is isomorphic to N.
In fact, S will be an independent subset of M, of size = rank M  rank N, and T will be a coindependent subset of M, of size = #((M/S).groundSet)  #N.groundSet, which is disjoint from S.
The output of this method should be the empty list iff the output of hasMinor is false (for the same input).






The object allMinors is a method function.