Make sure leases are maintained until release

Dnsmasq asks nova-dhcpbridge for existing leases on reboot, but
we don't return addresses that have been deallocated but not yet
released. This modifies nova to return leased but not allocated
addresses. It also delays removing the vif until we disassociate
the ip so we still have access to the mac address.

Resolves-bug: 1300355

Change-Id: Id78d66aad5005f052a1b49002de0ef13ef5a298d
libvirt: optimize pause mode support

Commit bfb28fcf9031af4c695177663702ce05edbbfa4d added a method
call that checks if the libvirt driver support the
VIR_DOMAIN_START_PAUSED flag. This patch optimizes that by reading
the value at startup.

Change-Id: I0fc1edec55df609ab25b9999f4a0d077ddcf0be7
Support multi-version pydevd

We need to support multi-version pydevd
in order to supporting pycharm3 and pydev3 remote debug.
If we want to remote debug by pydev3 or pycharm3,
"from pydev import pydev" is not work,
need to "import pydevd" directly.

Change-Id: I975c859c46f81d7fe1ca3dfebe05040153471800
Delete in-process snapshot when deleting instance

Try to delete the image created to hold the snapshot when the snapshot
creation fails because either the instance doesn't exist or it is in the
deleting task_state.

Closes-Bug: #1296590
Change-Id: I422c4f10c348d189fee217b55e0766e73eb5b16c
Remove quota-class logic from context and make unit tests pass

Continuation of quota-class removal started in
I1110022d6f628d03aaf363da707f2d2ef1600437.

Since we don't have an API to set quota-class any more, we don't need to
store it inside of the context. Also begin removing quota-class logic from
nova.quota to make test_quota pass with changes to context

Change-Id: I85dd24121a434b95dc6f0af180444d4258b50765
Code Improvement

Change code in wsgi.py.

Before:
if not is_dict(body[entity_name]):
    return False
return True

After:
return is_dict(body[entity_name])

Since this calling is in the end of the method I
can just return the result of the calling.

Change-Id: I834f26aa5a91abd18b8da10aef81f3aeb72a61ed
Merge "Delete in-process snapshot when deleting instance"
Merge "Support multi-version pydevd"
Merge "Remove quota-class logic from context and make unit tests pass"
Merge "Code Improvement"
Merge "libvirt: optimize pause mode support"
Merge "Make sure leases are maintained until release"