This is almost certainly the correct default for Dokku. While it's a BC break and might cause an increase in memory usage, the api is mostly internal and therefore this is safe to use.
This change makes interacting with port mappings more clear - folks might previously set the port mapping to the proxy type or vice-versa.
The existing proxy:ports* commands still exist but will show a deprecation warning for a single minor release.
This hopefully makes it a little easier to work with as the tooling is now based on something in golang core.
- move columnize usage to common plugin
- remove old vendor files
