Change log for galois-field

0.2.0

• Add deg for GaloisField
• Add order for GaloisField
• Add pow for GaloisField
• Add rnd for GaloisField

0.1.1

• Add Arbitrary instances to PrimeField, PolynomialRing, and ExtensionField.
• Add Bits instances to PrimeField.
• Add Pretty instances to PrimeField, PolynomialRing, and ExtensionField.
• Minor optimisations to multiplication and inversion with INLINE.

0.1.0

• Initial release.