packaging: mark default branch as development version
This help avoid confusion when installing version from the repository.
# define Mercurial extension metadata for evolution
#
# Copyright 2017 Pierre-Yves David <pierre-yves.david@ens-lyon.org>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
__version__ = '7.1.0.dev'
testedwith = '4.1.3 4.2.3 4.3.2 4.4'
minimumhgversion = '4.1'
buglink = 'https://bz.mercurial-scm.org/'