nix: package up an overlay for vpngate

nix/home.nix

@@ -130,7 +130,6 @@
       };
 
       initExtra = ''
-        export GOPATH=~/go
         export GPG_TTY=$(tty)
         export PATH=$PATH:~/.cargo/bin
         export PATH=$PATH:~/.local/bin
@@ -230,6 +229,13 @@
       };
     };
 
+
+    go = {
+      enable = true;
+      goBin = "go/bin";
+      goPath = "go";
+    };
+
     tmux = {
       enable = true;
       clock24 = true;