[EventLoop] Factory more implementations

Author: cboden

src/React/EventLoop/Factory.php

@@ -2,16 +2,17 @@
 
 namespace React\EventLoop;
 
-use React\EventLoop\StreamSelectLoop;
-use React\EventLoop\LibEventLoop;
-
 class Factory
 {
     public static function create()
     {
         // @codeCoverageIgnoreStart
         if (function_exists('event_base_new')) {
             return new LibEventLoop();
+        } else if (class_exists('libev\EventLoop')) {
+            return new LibEvLoop;
+        } else if (class_exists('EventBase')) {
+            return new ExtEventLoop;
         }
 
         return new StreamSelectLoop();