Move keys() methods in each resource class to FakeResource

FakeXXX classes in network don't need to fake any method,
except keys(). But keys() can be put in FakeResource since
it just returns all attributes in _info.

This patch moves removes all unnecessary fake methods code,
moves keys() method to FakeResource.

This patch also finds out some missing attributes in
network and router tests.

Change-Id: I799822c8715b9ac4f95b98f8350f196757d79d3e

Author: Tang Chen

openstackclient/tests/fakes.py

@@ -183,6 +183,9 @@ def __repr__(self):
         info = ", ".join("%s=%s" % (k, getattr(self, k)) for k in reprkeys)
         return "<%s %s>" % (self.__class__.__name__, info)
 
+    def keys(self):
+        return self._info.keys()
+
 
 class FakeResponse(requests.Response):