router navigation events are not covered in docs

stackoverflow question that lead to this issue being uncovered
https://stackoverflow.com/questions/48748721/showing-a-dialog-on-all-pages-after-rendering-is-done/49221583#49221583

we have an excelent blog post
https://ilikekillnerds.com/2015/09/understanding-aurelia-router-events/

and docs don't even mention it i think