hgext/zeroconf/__init__.py: Separate relative and absolute imports.

2to3 complains when relative and absolute imports are mixed, this fix just
separates them on the zeroconf extension. According to 2to3, the other modules
are fine.

hgext/zeroconf/__init__.py

@@ -23,7 +23,9 b' You can discover zeroconf enabled reposi'
   zc-test = http://example.com:8000/test
 '''
 
-import Zeroconf, socket, time, os
+import socket, time, os
+
+import Zeroconf
 from mercurial import ui, hg, encoding
 from mercurial import extensions
 from mercurial.hgweb import hgweb_mod