added swoole_async namespace class alias.
added swoole_async namespace class alias.

AJSoft/swoole-src,LinkedDestiny/swoole-src,LinkedDestiny/swoole-src,LinkedDestiny/swoole-src,LinkedDestiny/swoole-src,swoole/swoole-src,tutanhamon/swoole-src,tutanhamon/swoole-src,swoole/swoole-src,swoole/swoole-src,swoole/swoole-src,LinkedDestiny/swoole-src,AJSoft/swoole-src,tutanhamon/swoole-src,AJSoft/swoole-src,tutanhamon/swoole-src,swoole/swoole-src,LinkedDestiny/swoole-src,swoole/swoole-src,swoole/swoole-src,AJSoft/swoole-src,AJSoft/swoole-src,AJSoft/swoole-src,tutanhamon/swoole-src,tutanhamon/swoole-src,AJSoft/swoole-src,tutanhamon/swoole-src,LinkedDestiny/swoole-src