Author: David Mudrak
MDL-27508 introducing mod_workshop_renderer::perpage_selector()
http://git.moodle.org/gw?p=moodle.git;a=commit;h=5547b0dce12957894dd8c9a9ed1e6c479ffd8558
http://github.com/moodle/moodle/commit/5547b0dce12957894dd8c9a9ed1e6c479ffd8558
+ 2.3 en [showingperpage,mod_workshop]
+ 2.3 en [showingperpagechange,mod_workshop]