Missing constructor when raising NoNetworkAvailable

[Eugene Nikanorov]

code in type_tunnel.py type_vlan.py incorrectly throws exception class instead of exception class instance.

Some other places need to be fixed as well.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/118338

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/118338
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=3146837b7aea1a6c767131ad9aebaac2acb765df
Submitter: Jenkins
Branch: master

commit 3146837b7aea1a6c767131ad9aebaac2acb765df
Author: Eugene Nikanorov <email address hidden>
Date: Tue Sep 2 17:22:34 2014 +0400

    Throw exception instances instead of classes

    Prefer single style of throwing instances and not classes.

    Change-Id: If159afcd092de5381309cbe217d64145ed5b45b4
    Closes-Bug: #1364392