move ThreadException to pocketmine\thread namespace

src/thread/ThreadException.php

@@ -0,0 +1,28 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine\thread;
+
+class ThreadException extends \RuntimeException{
+
+}

src/thread/ThreadManager.php

@@ -81,7 +81,7 @@ class ThreadManager extends \Volatile{
 			try{
 				$thread->quit();
 				$logger->debug($thread->getThreadName() . " thread stopped successfully.");
-			}catch(\ThreadException $e){
+			}catch(ThreadException $e){
 				++$erroredThreads;
 				$logger->debug("Could not stop " . $thread->getThreadName() . " thread: " . $e->getMessage());
 			}