wordpress后台ajax.googleapis.com资源加载，影响后台加载速度，解决办法
function hc_cdn_callback($buffer) {
return str_replace('googleapis.com', 'useso.com', $buffer);
}
function hc_buffer_start() {
ob_start("hc_cdn_callback");
}
function izt_buffer_end() {
ob_end_flush();
}
add_action('init', 'hc_buffer_start');
add_action('shutdown', 'hc_buffer_end');
