Add syntax hints to readme

So it shows all the pretty colors.

Change-Id: I53fbb66d41f0c77f513638d4be72d6511f794d91
Reviewed-on: https://gerrit.causes.com/27329
Reviewed-by: Joe Lencioni <joe.lencioni@causes.com>
Tested-by: Joe Lencioni <joe.lencioni@causes.com>