gnupdate: Automatically download missing OpenPGP keys.
gnupdate: Automatically download missing OpenPGP keys.

* maintainers/scripts/gnu/gnupdate (%gpg-command, %openpgp-key-server):
  New variables.
  (gnupg-verify, gnupg-status-good-signature?,
  gnupg-status-missing-key?, gnupg-receive-keys, gnupg-verify*): New
  procedures.
  (fetch-gnu): Use `gnupg-verify*'.

svn path=/nixpkgs/trunk/; revision=29014

NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,triton/triton,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,triton/triton,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,triton/triton,SymbiFlow/nixpkgs,triton/triton,NixOS/nixpkgs,triton/triton,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,triton/triton,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,triton/triton,NixOS/nixpkgs,SymbiFlow/nixpkgs,triton/triton,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs