Notification of string changes

Author: Petr Škoda
MDL-36514 add new option to prevent only new self enrolments
Hopefully this will resolve all confusion around the enrol->status flag in this plugin.


http://git.moodle.org/gw?p=moodle.git;a=commit;h=e1fa177cf90ca1f8f487bb21c25248b41b73dbba
http://github.com/moodle/moodle/commit/e1fa177cf90ca1f8f487bb21c25248b41b73dbba

+ 2.5 en [newenrols,enrol_self]
+ 2.5 en [newenrols_desc,enrol_self]
+ 2.5 en [newenrols_help,enrol_self]
+ 2.5 en [status,enrol_self]
+ 2.5 en [status_desc,enrol_self]
+ 2.5 en [status_help,enrol_self]