2.6.3

• Fix correctness issue with range(), extract_from_if(), and retain_in(). If a RangeBounds
  with start > end was passed as an argument and start and end keys were stored in different
  internal pages in the database (i.e. a sufficient condition is that more than 4KiB of key-value
  pairs were between the two keys) then these methods would perform as if the argument had been
  start..