Support for traffic shaping / bandwidth quotas

We would like to use traffic shaping and bandwidth quotas to ensure predictable network behaviour in our virtualized hosting environment. The standard OpenStack Nova-libvirtd-qemu-kvm stack has support for this (by setting up token buckets on the tap interfaces), but the OpenContrail OpenStack integration effectively disables this by creating the tap interfaces as type=ethernet, which is deprecated for other reasons as well.

Please consider either and/or both of:

- Creating tap interfaces such that the standard OpenStack traffic shaping can be used (probably type=direct)
- Adding traffic shaping support within OpenContrail