[conformal/btcwire] a9293b: Add godoc reference badge to README.md.

[Dave Collins]

  Branch: refs/heads/master
  Home:   https://github.com/conformal/btcwire
  Commit: a9293bd32eb0480649a15961290c918050ededa3
      
https://github.com/conformal/btcwire/commit/a9293bd32eb0480649a15961290c918050ededa3
  Author: Dave Collins <da...@conformal.com>
  Date:   2014-04-19 (Sat, 19 Apr 2014)

  Changed paths:
    M README.md

  Log Message:
  -----------
  Add godoc reference badge to README.md.