Figure out a good option for escaping bound parameters

[kyrias]

In at least PostgreSQL you sometimes want to be able to use the {} array literal syntax, so we should offer a way to escape them.

[aleksanderkrauze]

Hi. I would like to reopen this discussion. I recently have found your crate and it proved quite useful for me. However inability of escaping curly braces is really inconvenient and forced me to do complex workarounds. I think the most natural way would be to use the same escaping as format_args macro does - {{ and }}. If you don't have time for implementing this, I could provide a PR for this feature.

[kyrias]

I think that's the style that I'd originally implemented but removed before the initial release. I feel like the rationale I provided for removing them was pretty weak though, and I can't think of a nicer syntax, so I guess I'd be fine with reïntroducing it.

You could probably just look at the two relevant commits in the commit history and file a PR that undoes them. :)