Bug#1050359: RM: gpr -- RoQA; dead upstream; depends on gtk2

[Till Kamppeter]

gpr is not only not upstream-maintained any more and depending oon the 
obsolete GTK2, it is also only used for printing with LPD/gnulpr/LPRng, 
all these being printing systems which are obsolete for near 2 decades 
(replaced by CUPS) and all not maintained upstream any more.

So it does not actually make sense any more to keep gpr in Debian. So I 
am in favor of its removal, too.