remove CamlinternalPr for compilation with OCaml 4.02.0
Revert "remove CamlinternalPr for compilation with OCaml 4.02.0"

This reverts commit c81ff0c5522b1c84a1b6a13b7525f065ebe816f9.
support comparison operator for prefilter on version
remove BatPrintf.CamlinternalPr for OCaml versions >= 4.02
Merge pull request #576 from vogler/master

remove CamlinternalPr for compilation with OCaml 4.02.0