i18n: mark help strings for translation
The gettext function is just another name for the normal _ function
and it is used for translating docstrings when using _ would make
pygettext.py output a warning.
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.