[WriteLog] more on highlighting callsigns

[David Hachadorian]

For a rtty callsign contained in the .dta database
to get highlighted by Writelog, the callsign needs to be
followed by a minimum of two characters.

So, if you have your callsign at the end of a
buffer message, it should be followed by two
spaces. One space plus a %R will also work.

Maybe Wayne can fix this behavior.

Dave Hachadorian, K6LL
Yuma, AZ