[aprssig] UIDIGI and new n-N

[Chris Kantarjiev]

For those running UIDIGI and not on the UIDIGI mailing list (and
for Bob's info and web page): a number of us have recently
discovered, the hard way, that the UIDIGI beacon offset setting
doesn't work correctly. Rather than providing an offset as 
expected, the value is simply added to the interval.

We haven't heard anything from Marco for a while, but
we hope there will be a fix forthcoming.

73 de chris KG6VYD