gendoc: group commands by category in man page and HTML help
Make Mercurial's man page and HTML help group commands by category, and
present the categories in a helpful order. `hg help` already does this;
this patch uses the same metadata.
This patch uses the same header level for command categories and for
commands. A subsequent patch will push the command headers down one
level.
Differential Revision: https://phab.mercurial-scm.org/D6326
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install::
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing::
$ make local # build for inplace usage
$ ./hg --version # should show the latest version
See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.