nascar-irc supports query_interval change on HUP

Modified nascar-irc SIGHUP handler to send an updateInterval request
to the new updateInterval handler in nascar-stats-scraper.
nascar-stats-scraper updateInterval method added

The updateInterval method will allow the calling program to request a
change to the refresh interval (how fast we hit the NASCAR JSON).

It also performs some basic sanity checking on the passed value and
will emit a WARNING event, and set the interval to 60sec, if non-sane
values are passed.