tc: Integrate Host QoS with network addition via setupNetworks

This patch makes it possible to leverage the network.tc package to
configure outbound Host network Quality of Service. The following
patch should add support for deleting the QoS entities when deleting
the associated network.

It is not legal to configure a shaped network over a device that
backs a non shaped network and vice-versa.

One can configure it just like this:

    In [1]:from vdsm import vdscli
    In [2]: c = vdscli.connect()
    In [3]: c.setupNetworks({
        'bar':{'nic': 'eth1',
        'qosOutbound': {
            'ls': {'m1': 4 * 1000 ** 2,
                   'd': 100 * 1000,
                   'm2': 3 * 1000 **2},
            'ul':{'m2': 8 * 1000 ** 2}},
        'defaultRoute': False,
        'bridged': False,
        'vlan': 11}}, {}, {'connectivityCheck': False})
    Out[3]: {'status': {'code': 0, 'message': 'Done'}}
    In [4]: c.getVdsCapabilities()['info']['networks']['bar']['qosOutbound']
    Out[4]:
    {'ls': {'d': 100000.0, 'm1': 4000000000.0, 'm2': 3000000.0},
     'ul': {'d': 0, 'm1': 0.0, 'm2': 8000000.0}}

Change-Id: I4a5378870a3dac9307a6eef8d9937a9c03a0c819
Signed-off-by: Antoni S. Puimedon <asegurap@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/30467
Reviewed-by: Dan Kenigsberg <danken@redhat.com>