Change bar_action handling to eliminate the need for bar_delay.
Old code called alarm() regularly and checked for input only at certain
times. Now, the file descriptor for reading the text is added to the
select() in the main loop, and so updates are caught immediately and
efficiently.
Patch submitted by Jason Woofenden <jason@jasonwoof.com>
(Note: Minor modifications were made to formatting and a dummy version
of the bar_delay option was added to avoid breaking old conf files.)