Add unix-compress decompression filter
Despite unix-compress has been considered obsolete since decades, it
is
still widely used in the GNSS community, for example to provide
Klobuchar
coefficients (see ftp://ftp.aiub.unibe.ch/CODE/2016/) or SP3 and clock
files
(see ftp://igs.ign.fr/pub/igs/products/mgex/1998/).
The decompression algorithm is quite simple and could probably be
added
easily as a predefined filter using the filtering mechanism described
in
issue #446).
(from redmine: issue id 447, created on 2018-04-27, closed on 2018-06-04)