Improved String.isPrefix etc.  These now use the bytevec_eq RTS call which is inlined on X86.  Also improved the single character case.  They're now small enough to be inline functions themselves.
Improved String.isPrefix etc.  These now use the bytevec_eq RTS call which is inlined on X86.  Also improved the single character case.  They're now small enough to be inline functions themselves.

git-svn-id: 98787b36aaefbae4b30fa755be920954cd25e1e4@1116 ae7d391e-3f74-4a2b-a0db-a8776840fd2a

dcjm/polyml,polyml/polyml,mn200/polyml,mn200/polyml,dcjm/polyml,polyml/polyml,polyml/polyml,mn200/polyml,mn200/polyml,polyml/polyml,dcjm/polyml,dcjm/polyml