Mikmatch 1.0.7 for ocaml 4.01

* new tophide 1.0.2 (not released) compatible with 4.01.0.  Minor inconsistency - ocamlfind package version is still 1.0.1

* mikmatch 1.0.7.  Installation by default is `mikmatch_str`.  `pcre-ocaml` is an optional dependency and `mikmatch_pcre` is installed if available.

* Tiny patch to META file so `mikmatch_str` does not depend on `pcre-ocaml`.

Ping @mjambon should he wish to comment.