Author: Damyon Wiese
MDL-44000 Atto: Add option to constrain image size
(Keep aspect ratio)
Also some small improvements to the edit image dialogue.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=ffb8aff65c7deeb422b3a7afd94f7a6c9f7c3172
http://github.com/moodle/moodle/commit/ffb8aff65c7deeb422b3a7afd94f7a6c9f7c3172
+ 2.7 en [constrain,atto_image]