Tests for Costco / Transform code

[rufuspollock]

Example problem

Try this demo:

http://reclinejs.com/demos/multiview/?url=http://data.london.gov.uk/datafiles/transport/tfl_passengers.csv&backend=dataproxy

Try to do the following transform:

function(doc) {
  doc['_noname_'] = doc['_noname_'].split(' - ')[0];
  return doc;
}

And the whole grid is empty!

[rufuspollock]

WONTFIX. transform / costco code is or should be going - see #349