Press the Green Merge button to merge a pull request.
Use the green button if you are confident that the changes are ok.
If you want to ensure that the pull request is ok, then I followed the guidelines outlined in https://help.github.com/articles/checking-out-pull-requests-locally
$> mkdir MASTER
$> cd MASTER
$> git clone git@github.com:picketlink/picketlink.git
$> cd picketlink
Now add some info into the .git/config file in the picketlink directory
$> vi .git/config
remote "origin"
fetch = +refs/heads/:refs/remotes/origin/
url = git@github.com:picketlink/picketlink.git
fetch = +refs/pull//head:refs/remotes/origin/pr/
The last line needs to be added.
git fetch origin
This will get you a lot of pull requests but your workspace is not updated yet.
git checkout pr/239
Your workspace branch will be now set to pr/239
If everything is ok, then go to github website and press the GREEN button.