Git commits in Moodle 2.8.8 by Alistair Spark

commit bb0c37afd43b972f93fd98289c3babbed57850b7
Author: Alistair Spark <aspark21@users.noreply.github.com>
Date:   Tue, 11 Aug 2015 17:13:48 +0800
Tag:    v2.8.8

MDL-50391 format_singleactivity: fix LTI Tool opens in existing window