MDL-44839 admin: Moved all system executable paths to config

AMOS BEGIN
 MOV ['gspath','assignfeedback_editpdf'],['pathtogs','admin']
 MOV ['gspath_help','assignfeedback_editpdf'],['pathtogs_help','admin']
AMOS END
MDL-40851 mod_forum: Final deprecation of forum_shorten_post
MDL-45568 events: fixed the description for the 'course_module_completion_updated' event
Merge branch 'wip-mdl-44839' of git://github.com/rajeshtaneja/moodle

Conflicts:
	lib/phpunit/bootstrap.php
Merge branch 'MDL-40851-master' of git://github.com/andrewnicols/moodle
Merge branch 'MDL-45568_master' of git://github.com/markn86/moodle
MDL-18162 mod_forum: Correct @param type in phpdoc to use stdClass
MDL-45625 mod_forum: Correct typo in upgrade notes
Merge branch 'MDL-18162-master-2' of git://github.com/andrewnicols/moodle
MDL-41665 mod_scorm: fixed broken report URLs
Merge branch 'MDL-41665_master' of https://github.com/markn86/moodle