[gnuoy,trivial] Pre-release charmhelper sync to pickup leadership election peer migration fix

hooks/charmhelpers/core/hookenv.py

@@ -34,7 +34,22 @@ import errno
 import tempfile
 from subprocess import CalledProcessError
 
-from charmhelpers.cli import cmdline
+try:
+    from charmhelpers.cli import cmdline
+except ImportError as e:
+    # due to the anti-pattern of partially synching charmhelpers directly
+    # into charms, it's possible that charmhelpers.cli is not available;
+    # if that's the case, they don't really care about using the cli anyway,
+    # so mock it out
+    if str(e) == 'No module named cli':
+        class cmdline(object):
+            @classmethod
+            def subcommand(cls, *args, **kwargs):
+                def _wrap(func):
+                    return func
+                return _wrap
+    else:
+        raise
 
 import six
 if not six.PY3: