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=2c643bb9882e127a2d8eaa3e205383da2f4fae76
http://github.com/moodle/moodle/commit/2c643bb9882e127a2d8eaa3e205383da2f4fae76
+ 3.5 en [application/json,core_mimetypes]