doc/common.txt

doc: use our own rst2man.py script (issue1746)

The rst2man tool has not yet been part of an official Docutils
release, and it is not present in most distributions. This poses a
problem for people who want to install Mercurial from source, or who
want to create a Mercurial package for such a distribution -- how to
specify the build-dependencies?

By including the rst2man.py script with Mercurial people only need a
normal Docutils installation in order to install Mercurial.

.. Common link and substitution definitions.

.. |hg(1)| replace:: **hg**\ (1)
.. _hg(1): hg.1.html
.. |hgrc(5)| replace:: **hgrc**\ (5)
.. _hgrc(5): hgrc.5.html
.. |hgignore(5)| replace:: **hgignore**\ (5)
.. _hgignore(5): hgignore.5.html