title: Floating IPs not released when deleting instance
body: <p>In Bluemix's VM Service, I've been creating instance using floating IPs from the Public-Network. Most of the time when I delete an instance, the IP is released. However, after a few weeks of testing, I see that 3 out of my 11 floating IPs are still allocated. Is there a way to unallocate them? To reiterate: I do <em>not</em> currently have any instances.</p>
  
  <p>This looks like the old bug here: <a href="https://bugs.launchpad.net/nova/+bug/997763" rel="nofollow">https://bugs.launchpad.net/nova/+bug/997763</a>, which was supposedly fixed in Folsom. </p>