localrepo: fix bugs in branchheads and add docstring
- The call to reverse() reversed the list in place in the global branchmap.
- The nodesbetween function doesn't preserve ordering.
Basic install:
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
See http://mercurial.selenic.com/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.