Documented how to read the badges

When first opening giddy up, I had no idea what I was looking at. After
some examination, I determined what the badges meant. I document my
findings so others may benefit.
Added pointer indicator to the cowboy

Turns out there's help there, but no idicator that it's clickable.
Merge pull request #67 from basho/mw-enhace-readme-badges

Documented how to read the badges