Remove accidentally committed vi .swp file.
Merge pull request #11391 from schuetzm/remove-swp-file

Remove accidentally committed vi .swp file.
Better not mutate the given options Hash
Add failing test for #9562

Rails 4.0.0 fails when trying to encode an ActiveSupport::TimeWithZone
that wraps a DateTime instance. This is fixed on master so add a test
to prevent regression.

(cherry picked from commit ad01b8da354268cebfae1519c28d19d75576ccb1)
Add missing require so that DateTime has the right superclass

If the DateTime core extensions were loaded before the Date core extensions
then you would get a superclass mismatch as DateTime hasn't been defined
yet so it gets set to Object by the acts_like core extension.

Fixes #11206