Migration to fix 2 issues at a time (#1 and #2). It changes both the name and type of the from and to attributes
We create aliases for from and to attribute, so we still are compatible with previous versions of the gem

Conflicts:

	app/models/refinery/calendar/event.rb
Removed mentions to 'from' and 'to' in scopes and sql queries

Conflicts:

	app/controllers/refinery/calendar/events_controller.rb
	app/models/refinery/calendar/event.rb
Since starts_at and ends_at attribute are date and time on_day scope has to be changed
Now that starts_at and ends_at are DateTimes we need to build the events in the tests with datetimes. Otherwise we could see some troubles with timezones and edge values (events at 12AM belonging to the previous day)

Conflicts:

	spec/requests/refinery/calendar/events/index_date_filters_spec.rb
	spec/requests/refinery/calendar/events/mini_calendar_spec.rb
New scopes starting_on_day and ends_on_day built with arel sintax and rewritten the on_day scope
Since we were cherrypickin from a branch with globalize I have introduces some globalize methods (my mistake)
Fixing issue #3: Migration now run properly on mysql
Merge pull request #38 from simplelogica/refinery_from-to

Changing from and to fields