Added a facade for defining the type of framework

Author: Andrey Helldar

Diff for: src/Facades/App.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace Helldar\LaravelSupport\Facades;
+
+use Helldar\LaravelSupport\Support\App as Support;
+use Illuminate\Support\Facades\Facade;
+
+/**
+ * @method static bool isLaravel()
+ * @method static bool isLumen()
+ */
+final class App extends Facade
+{
+    protected static function getFacadeAccessor()
+    {
+        return Support::class;
+    }
+}

Diff for: src/Support/App.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Helldar\LaravelSupport\Support;
+
+use Illuminate\Foundation\Application as LaravelApp;
+use Laravel\Lumen\Application as LumenApp;
+
+final class App
+{
+    public function isLaravel(): bool
+    {
+        return class_exists(LaravelApp::class);
+    }
+
+    public function isLumen(): bool
+    {
+        return class_exists(LumenApp::class);
+    }
+}