Remove the viewer side automatic logout after extended away time.
Note, however, that the server still logs you out after 30 minutes
away: see SVC 7251.
Allow more time (10 seconds vs 2 seconds) after initiating Away status
during which mouse movements do not remove the Away status.

I've done local testing with these changes.

For some reason I can't figure out, adding just these changes to the then-current viewer-development tip increased the likelihood (to something very close to 100%) of crashing due to problems with multi-threaded curl use.   There is a separate proposed fix for that (see STORM-1562), and integrating that proposed fix eliminated the problem and allowed me to test these changes.