Add a way to set quoting

[d33tah]

I just found the following in the code:

    let mut writer = csv::WriterBuilder::new()
        .quote_style(csv::QuoteStyle::Never)
        .delimiter(b',')
        .from_writer(out);

Why is QuoteStyle::Never there? Items containing commas break the writer by making CSV unreadable. Any chance you could expose some interface to override that?

[FabioBatSilva]

That sounds like a good idea..
Can't think of a good reason why that is there..

[d33tah]

Would you be OK with just getting rid of this line, changing the default?