Fixed for failing specs. 

PT chore: https://www.pivotaltracker.com/story/show/78230818

`rspec ./spec/views/events/show.html.erb_spec.rb:139 # events/show Hangouts for all users hangout has started renders Hangout details section`

`rspec ./spec/presenters/hangout_presenter_spec.rb:9 # HangoutPresenter all fields are present displays created time`
the 'UTC' is added automatically `created` and `updated` attributes of `:hangout` factory.