Allocating floating IPs on OpenStack may only partially succeed, not be deco'd on de-provision

[haxsaw]

Allocating a floating IP for a host on openstack is a two-part process: first, the IP must be allocated, and second, it must be associated with a server. It currently is possible to allocate the IP but fail to associate it with a server (if the IP was connect to a network that doesn't have a route to it), which causes the overall operation to fail. However, the FIP remains allocated, even though the process is considered to have failed.

What needs to happen is to treat this in a more transactional fashion: if the association fails, then the FIP should be released, and allow the failure to halt the provisioning process. This will ensure that everything will be in a consistent state such that teardown will release all allocated resources.