Macro writeable::impl_display_with_writeable

macro_rules! impl_display_with_writeable {
    (@display, $type:ty) => { ... };
    ($type:ty) => { ... };
}

Implements Display for types that implement Writeable.

It’s recommended to do this for every Writeable type, as it will add support for core::fmt features like fmt!, print!, write!, etc.

This macro also adds a concrete to_string function. This function will shadow the standard library ToString, using the more efficient writeable-based code path. To add only Display, use the @display macro variant.