discovery: move to new style import
This unify with the new core Mercurial usage and this will make future changes
to the imports easier to track.
--- a/hgext3rd/topic/discovery.py Wed Mar 30 03:44:47 2016 -0700
+++ b/hgext3rd/topic/discovery.py Wed Mar 30 03:44:59 2016 -0700
@@ -1,8 +1,14 @@
+from __future__ import absolute_import
+
import weakref
-from mercurial import branchmap
-from mercurial import error
-from mercurial import exchange
+
from mercurial.i18n import _
+from mercurial import (
+ branchmap,
+ error,
+ exchange,
+)
+
from . import topicmap
def _headssummary(orig, repo, remote, outgoing):