It is in the RST format, so this adds python-docutils as a build-dependency.

Signed-off-by: Sébastien Luttringer <sebastien.luttringer@smartjog.com>

With the permission of Romain Degez, CTO of Smartjog and Sébastien Luttringer.

Signed-off-by: Sébastien Luttringer <sebastien.luttringer@smartjog.com>

we need python-progressbar >= 2.3 to work with is.
We previously ship inside it because debian doesn't have 2.3 package available.
now we have built a debian package, we can remove code and add a dependency