Now that libcni has the ability to print a version message, plumb it
through correctly.
While we're at it,
- fix import paths
- run gofmt
- add some more comments to sample
- add container runtime swappability for release
host-local and static ipam plugins
tuning, bandwidth and portmap meta plugins
Utility functions created for common PrevResult checking
Fix windows build
This change improves the performance of the portmap plugin and fixes
hairpin, when a container is mapped back to itself.
Performance is improved by using a multiport test to reduce rule
traversal, and by using a masquerade mark.
Hairpin is fixed by enabling masquerading for hairpin traffic.