Merge #105

105: Add extra documentation for `delay` r=almindor a=Joeyh021

Took me a minute or two to figure out what value exactly to pass to `McycleDelay::new`, so figured I'd make a quick PR to add a note for anyone else that hits the same confusion as I did. Also added a doc line for the `delay` module while I was at it, as it was missing one.

Co-authored-by: Joey Harrison <joeyh021@icloud.com>