Author: Luca Bösch
MDL-63726 tool_dataprivacy: En-/disable 'Data retention summary' link
http://git.moodle.org/gw?p=moodle.git;a=commit;h=4f32e3af8c1b8b304cd4de8aef76e920cf09fc4f
http://github.com/moodle/moodle/commit/4f32e3af8c1b8b304cd4de8aef76e920cf09fc4f
+ 3.4 en [showdataretentionsummary,tool_dataprivacy]
+ 3.4 en [showdataretentionsummary_desc,tool_dataprivacy]