Rewrite installer without 3rd party installer lib.

resources/views/layouts/default/flash/message.blade.php

@@ -0,0 +1,24 @@
+@if (session()->has('flash_notification.message'))
+    @if (session()->has('flash_notification.overlay'))
+        @include('flash::modal', [
+            'modalClass' => 'flash-modal',
+            'title'      => session('flash_notification.title'),
+            'body'       => session('flash_notification.message')
+        ])
+    @else
+        <div class="alert
+                    alert-{{ session('flash_notification.level') }}
+                    {{ session()->has('flash_notification.important') ? 'alert-important' : '' }}"
+        >
+            @if(session()->has('flash_notification.important'))
+                <button type="button"
+                        class="close"
+                        data-dismiss="alert"
+                        aria-hidden="true"
+                >&times;</button>
+            @endif
+
+            {!! session('flash_notification.message') !!}
+        </div>
+    @endif
+@endif