New exchange checking in TLF

[Thomas Beierlein]

Hi all,

TLF just got an overhaul of the code to check and parse the qso
exchange. It should make the logic to recognize your exchange input
more robust. Thanks to Zoli HA5CQZ. 

In preparation for the ARRL SS coming next weekend we recommend to
give the new implementation a thorough test before starting the
contest. Please report back any problems or success stories.

Just keep a copy of your working source code to allow a reinstall in
case of severe problems.

73, 

-- 
"Do what is needful!"
Ursula LeGuin: Earthsea
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