Add capability to pass in comma separate string instead of file

[rayk47]

It would be nice if we the user could convert our own file to a string and then pass it to the library instead of a file being passed

[derekeder]

@rayk47 could you share more on the use case for this?

[erdihu]

@derekeder This would be useful for CSV strings that are returned from an API, for example. It's common to generate CSV data on the fly, often directly from the database and send them to a client; without saving the file.