Updating contributing

Author: bpassos-zz

README.md

@@ -419,5 +419,5 @@ lg = log --color --graph --pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s
 1. Fork it!
 2. Create your feature branch: `git checkout -b my-new-feature`
 3. Commit your changes: `git commit -m 'Add some feature'`
-4. Push to the branch: `git push origin my-new-feature`
+4. Push to the branch: `git push -u origin my-new-feature`
 5. Submit a pull request - cheers!