Nicer API for pushing single event?

[dpc]

To do some custom substition of output on certain events, I need use a for event in events { and then push some events (that I don't want to change), or write my custom stuff to the string directly.

Pushing a single element has a meh API:

renderer
    .push([event].into_iter(), &mut out)
    .expect("Can't fail");

🤷

If push was at least taking IntoIterator, then it would be better. Otherwise another trait method that does the [event].into_iter() would be nice.

[dpc]

Welp, judging by the panic I'm getting, maybe rendering certain events by myself like this might not work. But I'll figure out something.

[dpc]

Converting to #86