bump version to 0.4
Merge into master from pull request #21:
bump version to 0.4 (https://github.com/floodlight/ivs/pull/21)
Track the highest priority flow in each specific flowtable.

During match on key, if priority of the flow entry previously found is
greater than all flows in a given specific flowtable, then skip hashing into
the specific flowtable.
Bind ifname size to netdev interface name length
deliberately break ARP op matching
Merge into master from pull request #23:
Bind ifname size to netdev interface name length (https://github.com/floodlight/ivs/pull/23)
Addressed review comments.
max_priority -> cur_priority.
Merge into master from pull request #22:
Track the highest priority flow in each specific flowtable. (https://github.com/floodlight/ivs/pull/22)
Merge branch 'break-arp-op' of git://github.com/rlane/ivs
benchmarking with multiple flow masks