Add field "location" to acs_events: an event has now a place and a time.
This is a prerequisite for adding a "location" to the calendar.
- add location to acs_attributes
- recreate views "acs_events_dates" and "acs_events_activities"
to return location
- extend "acs_event__new()" (pg) and "acs_event.new()" (ora)
to accept location
- let handle "acs_event.new_instance()" the location attribute
- bump version number to 0.6.2d1
