JBAS-1665 return-to=self option; timeout repairs

JBAS-1665 return-to=self option; timeout repairs

Adds a special ?return-to=self parameter, telling the UI to return to
its own URL after completion / timeout / exit.

Rely solely on JS activity checker for page timeouts.  Otherwise, the
refresh simply overrides the activity checker.

Put all timeout value configuration into the template so no JS changes
are required for timeout changes.

Signed-off-by: Bill Erickson <berickxx@gmail.com>