Macro stringify_internal

macro_rules! stringify_internal {
    ($($t:tt)*) => { ... };
}

From https://github.com/tailhook/quick-error Changes:

• replace impl Error by impl Item::description
• $imeta Because of the #[macro_export(local_inner_macros)] usage on impl_error_chain_kind that macro will only look inside this crate for macros to invoke. So using stringify or write from the standard library will fail. Thus we here create simple wrappers for them that are not exported as local_inner_macros, and thus they can in turn use the standard library macros.