Force "use_vlan" to false on nova_fixed when using vlan modes

When ovs is used in vlan-mode quantums sets up an ovs-bridge to do the vlan
tagging. That bridge needs be attached to a none VLAN interface in order to
work correctly.

When linux-bridge is used quantum's linux bridge agent will create the correct
vlan interfaces automatically.
Add support for using the quantum cisco plugin
Add condition to ceilometer notifier in nova.conf
Ceilometer notifier will be added only if ceilometer is installed
Merge pull request #217 from rhafer/fix/ovs-vlan

https://github.com/crowbar/barclamp-nova/pull/217

Merged by devtool for ArkadyKanevsky
Merge pull request #223 from rhafer/fix/cisco-support

https://github.com/crowbar/barclamp-nova/pull/223

Merged by devtool for ArkadyKanevsky
Merge pull request #226 from MirantisDellCrowbar/DCB-158/pebbles/master

Add condition to ceilometer notifier in nova.conf