Function: ellweilpairing
Section: elliptic_curves
C-Name: ellweilpairing
Prototype: GGGG
Help: ellweilpairing(E, P, Q, m): computes the Weil pairing of the two points
 of m-torsion P and Q on the elliptic curve E.
Doc: Computes the Weil pairing of the two points of $m$-torsion $P$ and $Q$
 on the elliptic curve $E$.
