Notification of string changes

Author: Jun Pataleta
MDL-62414 tool_dataprivacy: Only show user's children in mydatarequests
* When coming from the DPO's "My data requests" page, don't show the
picker for other users (unless the DPO is a parent of another user).
* When creating a data request as a DPO, show a more appropriate
notification after redirecting back to the data requests page.


http://git.moodle.org/gw?p=moodle.git;a=commit;h=f946d875642473ebf4c6fc738760808121080a1c
http://github.com/moodle/moodle/commit/f946d875642473ebf4c6fc738760808121080a1c

+ 3.5 en [datarequestcreatedforuser,tool_dataprivacy]