http: len(x) fails if it doesn't fit into an int, use __len__() instead
len(x) raises OverflowError if it's bigger than 2**31-1, we need to call
__len__() ourself instead.
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.