branch heads: optimise computation of branch head cache (
issue1734)
The previous branch heads cache implementation iterated all ancestors
for each new revision in the repository, causing a massive slowdown on
cloning larger repositories.
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.