[project @ 2001-12-20 16:39:29 by simonmar]

[project @ 2001-12-20 16:39:29 by simonmar]
Now that we can derive arbitrary classes for newtypes, use this to
derive all the classes we need for the types in PrelCTypes and
PrelCTypesISO, instead of the previous hack of explicitly coercing the
methods.

This should improve the quality of code using these types too; the
coercions were surely getting in the way of optimisations before.