Revamp routing

All routes are now stored in a RouteCollection, which is then used
for dispatching by the (reusable) RouterMiddleware.

This change also entails moving all routes to the service providers.
This may be changed again later, and is done for convenience reasons
right now.

src/Http/RouteCollection.php

@@ -0,0 +1,83 @@
+<?php
+
+namespace Flarum\Http;
+
+use FastRoute\DataGenerator;
+use FastRoute\RouteParser;
+
+class RouteCollection
+{
+    /**
+     * @var array
+     */
+    protected $reverse = [];
+
+    /**
+     * @var DataGenerator
+     */
+    protected $dataGenerator;
+
+    /**
+     * @var RouteParser
+     */
+    protected $routeParser;
+
+    public function __construct()
+    {
+        $this->dataGenerator = new DataGenerator\GroupCountBased;
+        $this->routeParser = new RouteParser\Std;
+    }
+
+    public function get($path, $name, $handler)
+    {
+        return $this->addRoute('GET', $path, $name, $handler);
+    }
+
+    public function post($path, $name, $handler)
+    {
+        return $this->addRoute('POST', $path, $name, $handler);
+    }
+
+    public function put($path, $name, $handler)
+    {
+        return $this->addRoute('PUT', $path, $name, $handler);
+    }
+
+    public function delete($path, $name, $handler)
+    {
+        return $this->addRoute('DELETE', $path, $name, $handler);
+    }
+
+    public function addRoute($method, $path, $name, $handler)
+    {
+        $this->dataGenerator->addRoute(
+            $method,
+            $parsed = $this->routeParser->parse($path),
+            $handler
+        );
+
+        $this->reverse[$name] = $parsed;
+
+        return $this;
+    }
+
+    public function getRouteData()
+    {
+        return $this->dataGenerator->getData();
+    }
+
+    public function getPath($name, $parameters = [])
+    {
+        $parts = $this->reverse[$name];
+
+        $path = implode('', array_map(function ($part) use ($parameters) {
+            if (is_array($part)) {
+                $part = $parameters[$part[0]];
+            }
+            return $part;
+        }, $parts));
+
+        $path = '/' . ltrim($path, '/');
+        return $path;
+    }
+}