Laravel 5.6 updates

Travis config update

Removed HHVM script as Laravel no longer support HHVM after releasing 5.3

vendor/barryvdh/laravel-debugbar/src/LumenServiceProvider.php

@@ -14,7 +14,7 @@ class LumenServiceProvider extends ServiceProvider
      */
     protected function getRouter()
     {
-        return $this->app;
+        return $this->app->router;
     }
 
     /**
@@ -37,14 +37,6 @@ class LumenServiceProvider extends ServiceProvider
         $this->app->middleware([$middleware]);
     }
 
-    /**
-     * Check the App Debug status
-     */
-    protected function checkAppDebug()
-    {
-        return env('APP_DEBUG');
-    }
-
     /**
      * Get the services provided by the provider.
      *