I plan to later use uscan for simplifying package updates in some
NixPkgs packages. I have no code for that now.
I added Perl packages File::DesktopEntry and File::BaseDir in a slightly
hascky way because one part of the installation system replaced PREFIX=
with --prefix= and the other complained that it doesn't know what to do
with --prefix=. I checked that a script using File::DesktopEntry works,
and I don't know enough Perl to rewrite buildPerlPackage and hope that
my change is an improvement.
I removed trnaslated manpages because it uses po4a which has some more
Debian-specific dependencies of its own.