Order by clustering column.
Remove modifications to .gitignore
Add spec for correct ordering column
Order by column has to be a clustering column

RecordSet will fail fast if you try to reverse a record set that isn't scoped
to a single partition.
Merge branch 'order-by-clustering-column'

* order-by-clustering-column:
  Order by column has to be a clustering column
  Add spec for correct ordering column
  Remove modifications to .gitignore
  Order by clustering column.