[Cucumber Test Changes] Deferring the date test cases that cause failurs at night-time UTC

<a href="http://code.google.com/p/otwarchive/issues/detail?id=2542">Issue 2542</a>

Defers Scenarios: 
works/work_dates_edit.feature:7 # Scenario: Editing dates on a work
works/work_edit.feature:112 # Scenario: Editing a work you created today should not bump its revised-at date

I would appreciate a second opinion on the validity of the changes to make sure it is correct.