Added Ordering instances for HList
Added PartialOrdering instances for Coproduct
Adding at and apply to Sized
Merge pull request #153 from wheaties/sizedat

Adding at and apply to Sized
Merge pull request #147 from stacycurl/ordering

Added Ordering instances for HList & PartialOrdering instances for Coproduct
Added HList.permutations & Tuple.permutations