changegroup: cache changelog and manifestlog outside of loop
History has taught us that repo.changelog can add significant overhead
to loops. So cache the changelog instance outside of the loop to
avoid the lookup. While we're here, do the same for manifestlog,
since each loop would otherwise initialize a new manifestlog instance.
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.