Remove nixops examples and documentation

examples/nixops/node-libvirtd.nix

@@ -1,30 +0,0 @@
-{
-  bitcoin-node =
-    { config, pkgs, ... }:
-    {
-      deployment.targetEnv = "libvirtd";
-      deployment.libvirtd.memorySize = 8192; # megabytes
-      deployment.libvirtd.vcpu = 4; # number of cpus
-      deployment.libvirtd.headless = true;
-      deployment.libvirtd.baseImageSize = 400;
-      boot.kernelParams = [ "console=ttyS0,115200" ];
-      deployment.libvirtd.extraDevicesXML = ''
-        <serial type='pty'>
-          <target port='0'/>
-       </serial>
-        <console type='pty'>
-          <target type='serial' port='0'/>
-       </console>
-      '';
-      # Remove when fixed: https://github.com/NixOS/nixops/issues/931
-      system.activationScripts.nixops-vm-fix-931 = {
-        text = ''
-          if ls -l /nix/store | grep sudo | grep -q nogroup; then
-            mount -o remount,rw  /nix/store
-            chown -R root:nixbld /nix/store
-          fi
-        '';
-        deps = [];
-      };
-    };
-}

examples/nixops/node-vbox.nix

@@ -1,13 +0,0 @@
-{
-  bitcoin-node =
-    { config, pkgs, ... }:
-    {
-      deployment.targetEnv = "virtualbox";
-      deployment.virtualbox = {
-        memorySize = 4096; # megabytes
-        vcpu = 4; # number of cpus
-        disks.disk1.size = 358400; # 350 GiB
-        headless = true;
-      };
-    };
-}

examples/nixops/node.nix

@@ -1,5 +1,8 @@
+# This is an example network definition for deploying a nix-bitcoin node via NixOps.
+# NixOps deployment is currently untested.
+
 {
-  network.description = "Bitcoin Core node";
+  network.description = "Bitcoin node";
 
   bitcoin-node = { config, pkgs, lib, ... }: {
     imports = [
@@ -8,5 +11,9 @@
     ];
 
     nix-bitcoin.deployment.secretsDir = toString ../secrets;
+
+    #FIXME:
+    # Set `deployment.*` options like
+    # deployment.targetHost = "<address_or_hostname>";
   };
 }