OVSDriver: check packet-in in_port existence before using its upcall socket
OVSDriver: translate OVSP_LOCAL to OF_PORT_DEST_LOCAL when sending packet-in
OVSDriver: support packet-outs to OFPP_TABLE from OFPP_CONTROLLER

The packet-in unfortunately will still have in_port=OFPP_LOCAL. The only way I
see to fix this is to create another internal port, which I'm reluctant to do.
Merge into master from pull request #158:
fix packet-out to OFPP_TABLE from OFPP_CONTROLLER (https://github.com/floodlight/ivs/pull/158)