Author: Anupama Sarjoshi
MDL-77406 core: Logs to record user file uploaded in draft area
http://git.moodle.org/gw?p=moodle.git;a=commit;h=42f4b0a99100e9c050666d3ee3dd739663336c7e
http://github.com/moodle/moodle/commit/42f4b0a99100e9c050666d3ee3dd739663336c7e
+ 4.2 en [eventfileaddedtodraftarea,core_files]