[PATCH] Add image configuration option

["José Pekkarinen" <jose.pekkarinen@unikie.com>]

The following patch proposes to host nix configuration
files under nix folder that offers default configuration
for an image, defaulting to a release image, which would
be plain spectrum. A hardened default configuration will
be proposed in the near future. In case of configuration
collision between the default configuration and config.nix,
the latter will be taken into account.

Signed-off-by: José Pekkarinen <jose.pekkarinen@unikie.com>
---
 nix/eval-config.nix | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/nix/eval-config.nix b/nix/eval-config.nix
index 467f877..09a7ada 100644
--- a/nix/eval-config.nix
+++ b/nix/eval-config.nix
@@ -10,4 +10,5 @@
 
 ({ pkgs ? import <nixpkgs> {} }: {
   inherit pkgs;
-}) config
+}) (if config ? image && builtins.pathExists ./${config.image}.nix then
+      import ./${config.image}.nix else {}) // config
-- 
2.25.1