Reservation validation failing on Travis CI

[shippy]

Right now, there's a test that fails on Travis that we don't seem to be able to replicate locally (see, e.g. this build):

Failures:
  1) Reservation with blacked out start date fails appropriate validations
     Failure/Error: reservation.should_not be_start_date_is_not_blackout
       expected start_date_is_not_blackout? to return false, got true
     # ./spec/models/reservation_spec.rb:174:in `block (3 levels) in <top (required)>'
Finished in 1 minute 2.94 seconds
894 examples, 1 failure, 24 pending
Failed examples:
rspec ./spec/models/reservation_spec.rb:173 # Reservation with blacked out start date fails appropriate validations

[squidgetx]

#644