Bug#982287: wsjtx: Fails on launch

[Christoph Berg <myon@debian.org>]

Control: tags -1 confirmed
Control: retitle -1 wsjtx fails to start without en_US.UTF-8 locale

Re: Hilary Snaden
> On launch, the program immediately exits:
> 
> $ wsjtx
> Error: locale::facet::_S_create_c_locale name not valid

Oh, good catch. I had the same problem here but forgot to investigate
further after "apt install locales-all" had made the problem
disappear.

The problem is this in main():

      std::locale::global (std::locale ("en_US.UTF-8"));

I'll change that to C.UTF-8.

Until then, `dpkg-reconfigure locales` and enabling en_US.UTF-8 will
do the trick.

Christoph