Forward/Backward Step Navigation

[RileyMueller]

Issue

Currently when viewing a run, Go-To (the Arrow), and scrolling are the only ways to navigate between steps. This is fine for small runs but a significant irritant on larger runs. Looking at you "The Screaming Choir".

Feature Request

'Next Step' and 'Previous Step' buttons that appear when the n parameter (how Go-To works I believe?) is in use and increments or decrements and sends you to that page.