Re-apply pull request #4 from oracle2025

The PR shows as merged, but the commit is nowhere to be found in master.
Handle URLs not ending with "?"

Also handle URLs ending with or containing a ? by using an & instead.
Allow recovering from a fail

Currently, a web page refresh is required once the fail whale shows.  This lets it continue the normal refresh schedule so it can auto recover from a temporary server failure.
Remove dead code, there is no "#arrivals" element.

Since this repo began, the div's id is "departures"  not "arrivals" and the header is designed to display "FAIL WHALE" and stay visible, so don't try hiding it.