Fix pub sub mode

There is likely a better and more performant way to fix this but this works so far
and should be good enough to release and improve later.

Make test more robust

Add another test

lib/command.js

@@ -4,9 +4,19 @@
 // a named constructor helps it show up meaningfully in the V8 CPU profiler and in heap snapshots.
 function Command(command, args, callback) {
     this.command = command;
-    this.args = args;
+    this.args = args; // We only need the args for the offline commands => move them into another class. We need the number of args though for pub sub
     this.buffer_args = false;
     this.callback = callback;
+    this.sub_commands_left = args.length;
+}
+
+function OfflineCommand(command, args, callback) {
+    this.command = command;
+    this.args = args;
+    this.callback = callback;
 }
 
-module.exports = Command;
+module.exports = {
+    Command: Command,
+    OfflineCommand: OfflineCommand
+};