Author: Mihail Geshoski
MDL-41265 resource: Page resource option to show/hide last modified
http://git.moodle.org/gw?p=moodle.git;a=commit;h=f721ac68d4f30ee96bad7381eec8844dfc450f30
http://github.com/moodle/moodle/commit/f721ac68d4f30ee96bad7381eec8844dfc450f30
+ 3.6 en [printlastmodified,mod_page]
+ 3.6 en [printlastmodifiedexplain,mod_page]