First part of switching to OO style for walls
Add tests for URL generation when creating a wall
Add tests for email address passed to create wall
Add tests for design ID
Add initial Markdown version of API docs
Make TestSessions use the return value of create wall
Convert all tests over to new create wall behaviour
Remove old create wall wrapper
Switch get walls over to new walls code
Remove some dead code and update tests to look for latestSession
Update editor to match changes to API