Author: Victor Deniz
MDL-62320 mimetypes: Add JSON to the default mime types list
http://git.moodle.org/gw?p=moodle.git;a=commit;h=ab3759815a38c5249ac538e0b4283aac28f64a73
http://github.com/moodle/moodle/commit/ab3759815a38c5249ac538e0b4283aac28f64a73
+ 3.4 en [application/json,core_mimetypes]