Quaff function to detect filepath vs buffer inputs

Quaff:
> to drink (something, especially an alcoholic drink) heartily.

I think this is fitting name for a function that *actually ingests* a little bit of your file before telling you what its type/protocol is. Although this does imply a "drink first, smell later" mentality that I don't suggest taking in daily life.

@GretaCB any objection? If not I'll write tests and merge.

refs #10