contrib/compress: proper lock handling
Lock the src repo before beginning the compression and lock the destination
repo before copying the revlogs.
Proper handling of exceptions.
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.