Add new module for parsing/transforming/validating CSV data (or other kinds of delimited data)

Hi!

We have to process a lot of CSV files @MediaMath and the validation API is a perfect fit for doing this in a more type safe way.  This is a new module that adds validation capabilities to `Array[String]` which means you can use it with any CSV (or other delimiter) parser you want.  I also think this could be useful inside of Spark/Scalding data pipelines to create more strongly-typed data pipelines.

Hope you can include it, cheers!