remove emacs files
configure test db to use postgres
passing filter events by category feature

- revise Event.find_by_category to take variable number of Category names
as arguments
- add #category_field id to input field for easier reference in cucumber
test
- change build_list to create_list in for factory girl. create_list is
  supposed to save records in the database
- fix step_definitions should see events for categories, should see
  events for, and should see all events
- use :truncation option for database cleaner for out of the box support
  for multiple postgres connnections
s.t. here let's user authenticate in test mode

usually the user tables are dropped in test mode.
here the user can authenicate. I think it has to do with the fact that
omniauth is configured to be fake true.

TODO: delete this  commit