Author: Petr Škoda
MDL-34635 support multilang in self enrol course welcome message
Includes also new help string for the custom multilang placeholders by Helen Foster.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=56eda1f10a2c4ee481dd7a1717e8ec5307342e4d
http://github.com/moodle/moodle/commit/56eda1f10a2c4ee481dd7a1717e8ec5307342e4d
+ 2.3 en [customwelcomemessage_help,enrol_self]