Use Extensions to support direct file reading support like `CSV.read(dataset("..."))`

[mbauman]

It'd be great to overload some common file reader methods like CSV.read, JSON.read, Parquet.read, etc., to support reading directly from a ::DataSet reference. Having just a handful of these would drastically simplify the use of DataSets

[pankgeorg]

It'd be great to overload some common file reader methods like CSV.read, JSON.read, Parquet.read, etc., to support reading directly from a ::DataSet reference. Having just a handful of these would drastically simplify the use of DataSets

We can couple this with 1.9 and Weak Dependencies

[mortenpi]

This is a great idea, but I am a little bit concerned about pushing all these dependencies onto pre-1.9 users right now.