travis-ci improvements

[eytan-avisror]

Is this a BUG REPORT or FEATURE REQUEST?:
Feature Request

What happened:
Currently Travis CI only builds PRs, and pushes images post-merge. this is insufficient when wanting to test out a PR on a real cluster (or run bdd test)

What you expected to happen:

We should push an image even on PR, and use the commit hash as tag.
We should also run the BDD test nightly on governor:master and publish governor:nightly as a result.
We should consider some sort of hourly functional test as well