Author: Luca Bösch
MDL-63726 tool_dataprivacy: En-/disable 'Data retention summary' link
http://git.moodle.org/gw?p=moodle.git;a=commit;h=662878b6b5344c84944f4f50d8b0b79ab89ca5a0
http://github.com/moodle/moodle/commit/662878b6b5344c84944f4f50d8b0b79ab89ca5a0
+ 3.5 en [showdataretentionsummary,tool_dataprivacy]
+ 3.5 en [showdataretentionsummary_desc,tool_dataprivacy]