Downloading the ruamel.yaml source
==================================

ruamel.yaml is available as a Python package from PyPI.  However, this
does not include the unit tests.  These are available in the
SourceForge repository, but the repository does not have any tarballs
available for download.  So the watch file calls a local script to
clone the mercurial repository, check out the current tag, and pack it
into a tarball in place of the downloaded PyPI version.  This script
requires the mercurial package to be installed, but this is not a
build-dependency.