fix readme formatting [integrity#27 state:resolved]

README.markdown

@@ -33,9 +33,8 @@ Now you can go to http://localhost:4567, add your first project, and enjoy
 safer coding, with integrity.
 
 If you want automatic commit processing, you currently need to be using
-[GitHub](http://GitHub.com/ "GitHub - git repository hosting"). Click the edit
-link on your GitHub project, and add an integrity link that looks like the
-following to the `Post-Receive URL` field:
+[GitHub][]. Click the edit link on your GitHub project, and add an integrity
+link that looks like the following to the `Post-Receive URL` field:
 
     http://integrity.domain.tld/projectname/push
 
@@ -112,6 +111,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 [Campfire]: http://campfirenow.com
 [IRC]: http://wikipedia.org/wiki/IRC
 [CitrusByte]: http://citrusbyte.com
+[GitHub]: http://github.com
 
 [rspec]: http://rspec.info
 [rcov]: http://eigenclass.org/hiki.rb?rcov