Added Docker Build Status Badge to shields.io

Shields.io is a massive library of badges that can be inserted into project README’s or websites displaying various statuses (code coverage, health, version, etc).¬† Support for docker was missing the current build health, and was a pretty trivial addition.

Project link: https://github.com/badges/shields/pull/856

Nifty tech tag lists from Wouter Beeftink | Page content generated from commit: dffb2ec