Added MS-DOS 1.x and 2.0 directory listings (and fixed improper fault handling on 8086 machines)

modules/pcjs/lib/cpu.js

@@ -1025,6 +1025,14 @@ CPU.prototype.runCPU = function(fOnClick)
             catch(exception) {
                 if (typeof exception != "number") throw exception;
                 if (MAXDEBUG) this.println("CPU exception " + str.toHexByte(exception));
+                /*
+                 * TODO: If we ever get into a situation where every single instruction is generating a fault
+                 * (eg, if an 8088 executes opcode 0xFF 0xFF, which is incorrectly routed to fnFault() instead
+                 * of fnGRPUndefined()), the browser may hang because we're failing to yield often enough.
+                 * This is likely because the thrown exceptions are taking MUCH longer than normal instructions,
+                 * throwing off our burst calculations.  We need to either adjust the burst or break out of the
+                 * DO-WHILE loop on every exception.
+                 */
             }
 
             /*