Move aliases section in help below synopsis (issue362)
This should avoid confusion why e.g. "hg help co" shows help
for "hg update" instead.
Basic install:
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
See http://www.selenic.com/mercurial/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.