rust-filepatterns: call new Rust implementations from Python
This change adds the import to the `rust-cpython` bindings and uses
them when appropriate.
A wrapper function has been defined in the case of `_regex` to
keep this patch simple.
Differential Revision: https://phab.mercurial-scm.org/D6273
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install::
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing::
$ make local # build for inplace usage
$ ./hg --version # should show the latest version
See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.