[Nix-dev] cups update

[Marc Weber]

https://github.com/NixOS/nixpkgs/pull/1120

I can print nice on Canon bjc-like printers finally.

First I had to make gutenprintCVS compile (long time ago),
then cups still failed - it printed only 30% of some pages.

Last week I started giving it another try by trying to update cups.
Cups has undergone some changes:

  - pdf is the default filter chain (unless the printer supports gs or
    such)

  - some stuff got moved into cups-filters because Apple decided to no
    longer maintain it (openprinting took over)

  - cups has 2 configuration files now

  - probably some more eventually less important changes. You can read
    the changelog yourself.

gutenprintCVS is no longer neededed (by me) - but being able to build it
might be useful again. In that patch there are still some typos.

So consider giving the cups update a try and help me fix the remaining
things such as print "test page" - test different converters etc.

I've tested printing pdf files (openoffice and lpr) which works.
Printing .ps files does not work yet.

Should we keep both cups versions for a while? If so how, eg introduce
services.cups (old)  services.cupsNext (new) and allow using only one of
both?

Note: the gutenprint-cvs patch is not that important but could be useful
again.

Marc Weber