update to 2.3.1 version (build 388)

cleanup code and fix a bug

src/Custom/global_function.php

@@ -1,6 +1,11 @@
 <?php /** @noinspection PhpFullyQualifiedNameUsageInspection */ #plain
 
 //这里写你的全局函数
+/**
+ * @param callable $func
+ * @param string $name
+ * @noinspection PhpUnused
+ */
 function pgo(callable $func, $name = "default") {
     \ZM\Utils\CoroutinePool::go($func, $name);
 }