Dev fix: The end of the table needs a linear placement calculation like
the start.

Fix: If :first-child or :last-child is used on the TR elements in the
table's body, as is done in the new stylesheet for DataTables 1.10, the
row height calculated might be wrong.

- To address this the row height calculation function now ensures that
  three rows are added to the height calculation table and then the
  middle row is used for the size.
Fix: DataTables 1.10 compatiblity - when state saving check for Ajax
source form the new `ajax` property as well