[Xastir] Confirm on Exit

[Tom, ve7did]

Would it be possible to put the "Are You Sure" when exiting the 
program.  I recall it was in there many versions ago.  I have exited the 
program a couple of times over the past couple of years when not paying 
attention to what I was doing by being half a sleep or something.  It is 
maddening when you have had the uptime for a few (or more) months then 
mistakenly kill the program.  One of the nice things about linux/xastir 
is that it will keep running for a very long time (bragging rights over 
Windows...) providing the user (me) doesn't do something stupid.
I'm sure others have done it by mistake at times.

-- 
Propagation Knows No Boundaries
73 de Tom,  ve7did