Updated some DOS READMEs and made the onReset handler honor the running state of the CPU

modules/pcx86/lib/computer.js

@@ -1471,6 +1471,12 @@ class Computer extends Component {
          */
         if (!this.flags.powered || this.nPowerChange) return;
 
+        /*
+         * Whether or not we autoStart on reset should depend at least in part on whether we were running originally.
+         */
+        if (this.cpu) {
+            this.cpu.flags.autoStart = this.cpu.flags.running;
+        }
         /*
          * If this is a "resumable" machine (and it's not using a predefined state), then we overload the reset
          * operation to offer an explicit "save or discard" option first.  This is currently the only UI we offer to