Update drivers location and loading

- Extract much of server.php into a `Server` class
- Move all but the Laravel and Basic drivers into a subfolder
- Load all but the Laravel and Basic drivers via glob
- Add `beforeLoading` hook to simplify the `frontControllerPath` method for some drivers

cli/Valet/Drivers/Specific/JoomlaValetDriver.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace Valet\Drivers\Specific;
+
+use Valet\Drivers\BasicValetDriver;
+
+class JoomlaValetDriver extends BasicValetDriver
+{
+    /**
+     * Determine if the driver serves the request.
+     *
+     * @param  string  $sitePath
+     * @param  string  $siteName
+     * @param  string  $uri
+     * @return bool
+     */
+    public function serves(string $sitePath, string $siteName, string $uri): bool
+    {
+        return is_dir($sitePath.'/libraries/joomla');
+    }
+
+    /**
+     * Take any steps necessary before loading the front controller for this driver.
+     *
+     * @param  string $sitePath
+     * @param  string $siteName
+     * @param  string $uri
+     * @return void
+     */
+    public function beforeLoading(string $sitePath, string $siteName, string $uri): void
+    {
+        $_SERVER['PHP_SELF'] = $uri;
+    }
+}