py2: remove simple from __future__ statements
These were needed for Python 2 support. Now that our linter no longer
mandates these, we can start deleting them.
Differential Revision: https://phab.mercurial-scm.org/D12254
{
"conduit_uri": "https://phab.mercurial-scm.org/api",
"phabricator.uri": "https://phab.mercurial-scm.org/",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}