Export data to CSV

[nicoespeon]

Someone suggested to be able to export graph data into a CSV so we can replicate the report in spreadsheets.

---

What we would need:

• A stream of button clicks.
• A stream containing information to download.
• withLatestFrom to retrieve latest value whenever there is a click.
• Map over resulted stream to preformat data to be the input of the driver.
• A driver that deals with CSV conversion and download, given a stream of pre-formatted arrays.

return {
  // … drivers
  exportToCsv: Observable.withLatestFrom(
    clicks$,
    trelloData$.map(parseToCsvData),
    (clicks, data) => data
  )
}