Whitespace changes.
Adds a comma back into journal formatter registration.

This one somehow got lost. But it definitely belongs here.
Removes acts_as_tree from planning elements.
Changes recycle bin to be triggered w/ trash.

Previously, destroy! would do what destroy formerly did, and destroy
would move to trash. Now trash trashes stuff into the recycle bin and
destroy destroys from DB.
Removes obsolete validation.
Removes obsolete method override.
Fixes remaining spec for circular structures.
Updates changelog.
Removes obsolete spec.

Testing circular dependencies is part of awesome_nested_set. Also, this
test is rather bad catching StaleObjectErrors.
Merge pull request #256 from opf/feature/no_more_acts_as_tree

No more acts_as_tree in planning elements.