scala.js support

[minettiandrea]

Hi Toshiyuki,

I've used your library in many projects, recently I've been using scala.js quite a lot and I was missing a good csv library so I've tried to do a porting of your library, and actually it was quite simple so here the pull request.

It didn't changed the API for the JVM, i've just added an object CSV to access read and write directly (without writing or reading a file).

The method in CSV are:

def read(input: String)(implicit format: CSVFormat): List[List[String]]
def writeAll(input: Seq[Seq[String]])(implicit format: CSVFormat): String
def writeRow(input: Seq[String])(implicit format: CSVFormat): String 

It would be great if you could merge my pull request and release it on the maven repository, I guess also for the library to be listed between the libraries that are supporting scala.js would be a good visibility.

Regards and thank you for your great work

Andrea