use http request cleaner instead of pool cleaner for subscriber request cleanup
use http request cleaner instead of pool cleaner for subscriber request cleanup

flybird119/nginx_http_push_module,flybird119/nginx_http_push_module,h0x91b/nginx_http_push_module,h0x91b/nginx_http_push_module,h0x91b/nginx_http_push_module,slact/nginx_http_push_module,lzpfmh/nginx_http_push_module,lzpfmh/nginx_http_push_module,flybird119/nginx_http_push_module,slact/nginx_http_push_module,lzpfmh/nginx_http_push_module,slact/nginx_http_push_module,h0x91b/nginx_http_push_module,slact/nginx_http_push_module,flybird119/nginx_http_push_module,lzpfmh/nginx_http_push_module