Fix 80 char. error

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)

README.md

@@ -184,7 +184,8 @@ Want to hack on Docker? Awesome! There are instructions to get you
 started [here](CONTRIBUTING.md). If you'd like to contribute to the
 documentation, please take a look at this [README.md](https://github.com/docker/docker/blob/master/docs/README.md).
 
-These instructions are probably not perfect, please let us know if anything feels wrong or incomplete.
+These instructions are probably not perfect, please let us know if anything
+feels wrong or incomplete.
 
 ### Legal