全局帮助方法

• dump( mixed $arg, [, mixed $...] )
• dumpdie( mixed $arg, [, mixed $...] )
• run_info($verbose = false)
• wlog($name, $value)
• show_404()
• show_success($message, $url = '', $wait = 6)
• show_error($message, $url = '', $wait = 6)
• R($url, $wait = 0, $message = '')
• getv($key, $default = '', $callback = '')
• getp($pos, $default = '', $callback = '')
• postv($key, $default = '', $callback = '')
• requestv($key, $default = '', $callback = '')