Hide default Floating IPs quotas with Neutron

It is not possible to access the default quotas via an API for
Neutron. Remove the quota in that case for now, as it comes from Nova
and could cause confusion.

Partial-Bug: #1109140

Change-Id: If8df21b4ecbe541ce53790578820e22f36c32260
Always display the Domains panel for Keystone V3

The Domains panel is only displayed when the user explicitly set
the OPENSTACK_KEYSTONE_MULTIDOMAIN_SUPPORT to True and keystone
supports V3.

The change allows the Domain panel to be displayed even if the flag
OPENSTACK_KEYSTONE_MULTIDOMAIN_SUPPORT is False. In this case, the
CRUD actions will not be available in the panel.

If the local_settings.py.example is taken as is, Keystone V3 is
assumed to be available. The Domain panel should also be available.

Change-Id: Ifa81c6f106ba98a192a163aeb80f0ff92888d954
Fixes: bug 1211667
Merge "Hide default Floating IPs quotas with Neutron"
Merge "Always display the Domains panel for Keystone V3"