Updated TYPE_MAP for security group rules

Updated TYPE_MAP for security group rules so that from_port and
to_port are correctly identified as ints for XML.

Fixed bug:1160238

Change-Id: I432c7f01fc16c476d6452a4ac4e219dbfa6d0388

reddwarfclient/xml.py

@@ -50,6 +50,10 @@ TYPE_MAP = {
         "vmRss": int,
         "fdSize": int,
     },
+    "security_group_rule": {
+        "from_port": int,
+        "to_port": int,
+    },
 }
 TYPE_MAP["flavors"] = TYPE_MAP["flavor"]