[feature request] support json as conversion format or better csv support

[rchevallier]

csv export is nice, but if a text field contains itself the separator, the output then cannot be correctly interpreted

1. Exporting as JSON would alleviate the problem

2. Another possibility is to export the CSV with options:

• adding quote to all string field ouput (and quoting the quote as "")
• specifying a different custom separator (eg using some improbable character or set of character as separator: ¤µ§)