Created originally on Bitbucket by WheeleD (David Wheeler)
Changesets for this Pull Request have not been imported, because it had been already declined on Bitbucket. Marked as closed by the import user.
- Revised method of constructing borders for merged cells to eliminate the creation of spurious border styles (apart from the top left cell style which stores the border style for the entire range). Necessitated a change to _side_for_edge method and so the corresponding test_side_for_edge has been modified to suit.