add auto update feature

app/Listeners/Updates/Listener.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace Laraspace\Listeners\Updates;
+
+class Listener
+{
+    const ALIAS = '';
+
+    const VERSION = '';
+
+    /**
+     * Check if should listen.
+     *
+     * @param  $event
+     * @return boolean
+     */
+    protected function check($event)
+    {
+        // Apply only to the specified alias
+        if ($event->alias != static::ALIAS) {
+            return false;
+        }
+
+        // Do not apply to the same or newer versions
+        if (version_compare($event->old, static::VERSION, '>=')) {
+            return false;
+        }
+
+        return true;
+    }
+}

app/Listeners/Updates/V10/Version101.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Laraspace\Listeners\Updates\V10;
+
+use Illuminate\Contracts\Queue\ShouldQueue;
+use Illuminate\Queue\InteractsWithQueue;
+use Laraspace\Listeners\Updates\Listener;
+use Laraspace\Events\UpdateFinished;
+
+class Version101 extends Listener
+{
+    const ALIAS = 'core';
+
+    const VERSION = '1.0.1';
+
+    /**
+     * Handle the event.
+     *
+     * @param  object  $event
+     * @return void
+     */
+    public function handle(UpdateFinished $event)
+    {
+        if (!$this->check($event)) {
+            return;
+        }
+    }
+}