Add Route extender for registering routes with forum, admin or API

src/Extend/Route.php

@@ -0,0 +1,49 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Extend;
+
+use Flarum\Http\RouteCollection;
+use Flarum\Http\RouteHandlerFactory;
+use Illuminate\Contracts\Container\Container;
+
+class Route implements Extender
+{
+    protected $appName;
+    protected $name;
+    protected $httpMethod;
+    protected $path;
+    protected $handler;
+
+    public function __construct($appName, $name, $httpMethod, $path, $handler)
+    {
+        $this->appName = $appName;
+        $this->name = $name;
+        $this->httpMethod = $httpMethod;
+        $this->path = $path;
+        $this->handler = $handler;
+    }
+
+    public function apply(Container $container)
+    {
+        /** @var RouteCollection $routes */
+        $collection = $container->make("flarum.{$this->appName}.routes");
+
+        /** @var RouteHandlerFactory $factory */
+        $factory = $container->make(RouteHandlerFactory::class);
+
+        $collection->{$this->httpMethod}(
+            $this->path,
+            $this->name,
+            $factory->toController($this->handler)
+        );
+    }
+}