Author: Luca Bösch
MDL-63726 tool_dataprivacy: En-/disable 'Data retention summary' link
http://git.moodle.org/gw?p=moodle.git;a=commit;h=abc469dd3b601c98125164e83e2142391983146f
http://github.com/moodle/moodle/commit/abc469dd3b601c98125164e83e2142391983146f
+ 3.6 en [showdataretentionsummary,tool_dataprivacy]
+ 3.6 en [showdataretentionsummary_desc,tool_dataprivacy]