Bas van Dijk 527781ebc4 apache-httpd: fix nix evaluation error
This only sets the timezone when it's not null to prevent:

  error: cannot coerce null to a string, at
  nixpkgs/nixos/modules/services/web-servers/apache-httpd/default.nix:676:7
2017-10-31 17:33:54 +01:00
..
2017-03-06 15:54:50 +01:00

*** NixOS ***

NixOS is a Linux distribution based on the purely functional package
management system Nix.  More information can be found at
http://nixos.org/nixos and in the manual in doc/manual.