Update README

Initially, when I tried to check the TravisCI link to check the build error it took me to the actual image rather than the TravisCI page hence whilst I changed that I went ahead and added a RubyGems Badge and a CodeClimate badge.

I also added an animated gif for the demo which links to the video still.

You can see a preview here:
https://github.com/BukhariH/fuubar/blob/fad584562a11cc097ee6cfe6eefeffbeb44b1107/README.md