[jhc] jhc type inference algorithm

Oh, this might be useful: http://research.microsoft.com/~simonpj/papers/boxy/ Originally jhc's type and kind inference algorithm was based on the one from the 'typing haskell in haskell' paper. Now they are both brand new implementations based on SPJ's boxy type inference algorithm explained in the above paper. Among other advantages, this gives me existentials, rank-n polymorphism, better error messages, and polymorphic unboxed values[1]. I also find it more elegant and is a few thousand less lines of code. [1]. A jhc exclusive! John -- John Meacham - ⑆repetae.net⑆john⑈