Update concat-dependencies Dockerfile

[yusefnapora]

This updates the concat-dependencies Dockerfile:

• update go base image 1.7.3 from 1.7.1
• use standard setup.sh script

Since this is based on the latest master, it gets the most recent gx dependencies. It's already pushed to Docker hub, and I removed the Travis environment variable that skips the integration tests, so this seems to have fixed up our CI mess.