Add gcc to jupyter path

machines/kcnhub/servers/jupyterhub.nix

@@ -7,7 +7,15 @@
     extraConfig = ''
       c.SystemdSpawner.mem_limit = '2G'
       c.SystemdSpawner.cpu_limit = 1.0
+      c.SystemdSpawner.extra_paths = ['${pkgs.buildEnv {
+                                     name = "jupyterhub-system-spawner-env";
+                                     paths = with pkgs; [
+                                       gcc
+                                     ];
+                                   }}/bin']
     '';
+    # Extra Paths used to add gcc et al for packages like Brian2
+    # https://github.com/jupyterhub/systemdspawner#extra_paths
 
     kernels = {
       python3 = let