Configuration for quote style of strings about stylua

[Dekkonot]

I'm in favor of adding a configuration and I think forcing it is good.

I can't see it being desirable to swap out string styles to avoid as many string escapes as possible. That seems to go in the face of "consistency" and is really only applicable to \" and \', neither of which are particularly common -- it's been quite a while since I've used "\"" for anything outside of side projects.

[LastTalon]

I tend to agree with prettier's string rationale. The whole point of using a formatter is that the computer can make these changes when people are unable/unwilling and do it correctly every time. So I'd rather the formatter aim to reduce the amount of escaping in the string as much as possible.

I'll agree with how they do prettier's option as well here. And I think the option for configuration is a good idea in this case.

[JohnnyMorganz]

#73 will add support for this configuration. I have decided to default to preferring double quotes, but not forcing it. I did this so it falls in line with other similar formatters, like prettier. The original behaviour is still available by setting quote_style = "ForceDouble" in a config