FEATURE: `format!` macro equivalent

[JakubKoralewski]

What do you think of having a format_tiny! macro? I could try it.

It would probably look a bit different as I think the string based "{}" approach is a compiler intrinsic.

[ThatsNoMoon]

Sorry for the delay (I thought I would get notifications for this repo); that sounds like a solid addition to me. I think it should be fairly easy to implement as TinyString/ArrayString already implement std::fmt::Write. Such a macro should also allow specification of the type of backing array to use, like tinyvec's macros do.

The naming seems like it might be the most difficult part, my initial thought was tiny_format! and array_format!, but I'm not sure if there are better options or not.

I'll get to this when I have some more free time, otherwise I'll try to review any PRs ASAP.