Speed up functions in the "power" module.

[corywalker]

Depends on #54, according to testing.

PolynomialQuotientRemainder[(-108 - 108x + 207x^2 + 239x^3 - 81x^4 - 153x^5 - 27x^6 + 21x^7 + 9x^8 + x^9),(-9 - 6x + 8x^2 + 6*x^3 + x^4), x]

can take too long.