the header matches the number of inputCols which is 8
I append an output, so there should be 9 cols. h2o parses it as 8 cols because the header is short on.
the test fails now (it was comparing the wrong # of cols before)
I also cleaned up how it creates a pair of random rows for the dataset creation . Output col is still appended separately and fully random.

I think h2o should complain here, not just drop a col silently. (because of the mismatched header..i.e. what the test name is saying it's testing