Add WIP docker support

docker.nix

@@ -0,0 +1,22 @@
+# Builds a docker image with latest neuron from master branch.
+# Run as:
+#   docker load -i $(nix-build docker.nix)
+let
+  pkgs = import <nixpkgs> {};
+  baseImage = pkgs.dockerTools.pullImage {
+    imageName = "lnl7/nix";
+    finalImageTag = "2.3.3";
+    imageDigest = "sha256:a969b4f238eab9298fe426fc90cc45efe01685431a419ca2907f10ddbbed2b7f";
+    sha256 = "1zy4zwlka5c4hgjbgy8xh1ikyb3z2lwzfjwv8y0cyzx1danys4vk";
+  };
+  neuron =
+    let src = builtins.fetchGit { url = "https://github.com/srid/neuron"; ref = "master"; };
+    in import src.outPath { gitRev = src.shortRev; };
+in
+
+pkgs.dockerTools.buildImage {
+  fromImage = baseImage;
+  name = "sridca/neuron";
+  tag = "test";
+  contents = [ neuron ];
+}