Proactively notify the user when their session has timed out

[chrisala]

MERIT runs a 5 minute interval "keep alive" ping to the server.
This feature enhances that mechanism to notify the user when their session has timed out and prompting them to login again.

It should only do this for an authenticated session (rather than a HTTP session created for an anonymous user)

If the keep alive ping returns 401/403, display a banner at the top of the page that informs the user the session has timed out and provides a link to re-login (in a new window).

After logging in, the banner should be removed.

If the keep alive ping indicates a dead network (maybe a status code of 0), display a banner informing the user the network connection is lost.