Author: Daniel Neis Araujo
MDL-44484 admin: Allow theme field in upload users tool
http://git.moodle.org/gw?p=moodle.git;a=commit;h=09df5975970f1983f00faa9febb48492a621da00
http://github.com/moodle/moodle/commit/09df5975970f1983f00faa9febb48492a621da00
+ 3.7 en [invalidfieldvalue,core_error]
+ 3.7 en [invalidtheme,core_error]