Add support for integrating into nix/nixos

nix/configuration-test.nix

@@ -0,0 +1,52 @@
+{ config, pkgs, ... }:
+let
+  docspell = import ./release.nix;
+in
+{
+  imports = docspell.modules;
+
+  i18n = {
+    consoleKeyMap = "neo";
+    defaultLocale = "en_US.UTF-8";
+  };
+
+  users.users.root = {
+    password = "root";
+  };
+
+  nixpkgs = {
+    config = {
+      packageOverrides = pkgs:
+        let
+          callPackage = pkgs.lib.callPackageWith(custom // pkgs);
+          custom = {
+            docspell = callPackage (docspell.pkg "0.2.0") {};
+          };
+        in custom;
+    };
+  };
+
+  services.docspell-joex = {
+    enable = true;
+    base-url = "http://docspelltest:7878";
+  };
+  services.docspell-restserver = {
+    enable = true;
+  };
+  services.docspell-consumedir = {
+    enable = true;
+    watchDirs = ["/tmp/test"];
+    urls = ["http://localhost:7880/api/v1/open/upload/item/blabla"];
+  };
+
+  services.xserver = {
+    enable = false;
+  };
+
+  networking = {
+    hostName = "docspelltest";
+  };
+
+  system.stateVersion = "19.09";
+
+}