Data package for math/pari.

Needed by ellap and ellcard for large primes.

These polynomials were extracted from the ECHIDNA databases and
computed by David R. Kohel.  This covers finite fields of cardinality q
up to 750 bits.  PARI/GP 2.9 contains fallback code to go on when all
modular polynomials in the database have been exhausted and can handle
larger fields (with an important slowdown).