ovs-docker: Enhance documentation to handle pre-programmed interfaces.

Currently, Controllers and CMSes that integrate with Open vSwitch
after following the IntegrationGuide.md, expect to start VMs after
the underlying network infrastructure is ready. I have been asked
a few times on how to handle the same with containers. This commit
provides documentation on one way to achieve it.

Signed-off-by: Gurucharan Shetty <gshetty@nicira.com>
Acked-by: Thomas Graf <tgraf@noironetworks.com>
ovs-docker: Ability to set the default gateway.

ovs-docker currently lets one add the ability to set the
IP address on an OVS interface. Ability to set the default
gateway too can be an useful addition. (orchestrators
who plan to use OVS interfaces can do this from a single
utility instead of multiple utilities)

Requested-by: Marvin Pascual <marvin@pascual.com.ph>
Signed-off-by: Gurucharan Shetty <gshetty@nicira.com>
Acked-by: Thomas Graf <tgraf@noironetworks.com>
ovs-docker: Add the ability to set VLANs.

For containers containing multiple ports and spawned by
orchestrators without openflow flows configured, it can be quite
useful to distinguish their traffic with vlans. This can be useful
when containers are spawned inside VMs instead of hypervisors.

Signed-off-by: Gurucharan Shetty <gshetty@nicira.com>
Acked-by: Thomas Graf <tgraf@noironetworks.com>
dpctl: Add support for using UFID to add/del flows.

Parse "ufid:<foo>" at the beginning of a flow specification and use it
for flow manipulation if present.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>