This adds the functionality for Travis to sync with http://kompose.io in
regards to "syncing" the docs directory in master and the docs within
gh-pages.
Two things are added:
script/sync-docs/sh
script/deploy_key.enc
The encrypted key follows the conventions here:
https://gist.github.com/domenic/ec8b0fc8ab45f39403dd
and the functionality of running: `travis encrypt-file encrypt_key`
The script is ran each-time a PR is merged (and only if it's
sucessful!) as per the modifications in `.travis.yml`.
Thus each time we make a change in master, there's no need to open up
another PR for syncing the changes with `gh-pages`.