compat: drop compatibility for Mercurial <= 4.0
We are dropping compatibility with older mercurial version. This will help us
to clean up the code base.
# 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__ = '7.0.0.dev'
testedwith = '4.1.3 4.2.3 4.3.2 4.4'
minimumhgversion = '3.8'
buglink = 'https://bz.mercurial-scm.org/'