keyword: make main class and hg command accessible
Switch from global vars to top level dictionary.
Goal: make it easier for external tools (like tortoisehg)
to hook into keyword extension.
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.