Notification of string changes

Author: Mihail Geshoski
MDL-61731 message_email: Add privacy files and unit tests


http://git.moodle.org/gw?p=moodle.git;a=commit;h=db6aacf45e84be38dd11e15c4fb519fa976e9b7b
http://github.com/moodle/moodle/commit/db6aacf45e84be38dd11e15c4fb519fa976e9b7b

+ 3.4 en [privacy:metadata:attachment,message_email]
+ 3.4 en [privacy:metadata:attachname,message_email]
+ 3.4 en [privacy:metadata:externalpurpose,message_email]
+ 3.4 en [privacy:metadata:fullmessage,message_email]
+ 3.4 en [privacy:metadata:fullmessagehtml,message_email]
+ 3.4 en [privacy:metadata:recipient,message_email]
+ 3.4 en [privacy:metadata:replyto,message_email]
+ 3.4 en [privacy:metadata:replytoname,message_email]
+ 3.4 en [privacy:metadata:subject,message_email]
+ 3.4 en [privacy:metadata:userfrom,message_email]