moved floating ip db access and sanity checking from network api into network manager

added floating ip get by fixed address
added fixed_ip_get
moved floating ip testing from osapi into the network tests where they
belong

Change-Id: I3ee53971206e37405a2adc2491412f7896e1af87

nova/test.py

@@ -56,6 +56,7 @@ LOG = log.getLogger('nova.tests')
 
 class skip_test(object):
     """Decorator that skips a test."""
+    # TODO(tr3buchet): remember forever what comstud did here
     def __init__(self, msg):
         self.message = msg