Sta mapping locations

Took the execution of create_frost_views() outside of user_exists() check to always update the frost views on calling the dispatcher action.

Made some changes to THINGS and SENSORS:

• remove coalesce(nullif(..., ''), ' ') statements
• only show things and sensors where a static_location or a dynamic location exists
• group by configuration.id (was needed after joining the location actions)

Included LOCATIONS, HIST_LOCATIONS, LOCATIONS_HIST_LOCATIONS, THINGS_LOCATIONS