Merge pull request #5701 from minrk/ssh-docstring

add external.ssh.__init__

IPython/external/ssh/__init__.py

@@ -0,0 +1,7 b''
+"""This is a copy of zmq.ssh"""
+
+try:
+    from zmq.ssh import *
+except ImportError:
+    from . import tunnel
+    from .tunnel import *