def all_within(lat, long, dist)
      @data.select { |d| d.distance_from(lat, long) < dist }
    end
def all_within(lat, long, dist)
      @data.select { |d| d.distance_from(lat, long) < dist }
    end
Returns every object within dist (miles)
 of lat/long

 @param  lat [Float] [A latitude position]
 @param  long [Float] [A longitude position]
 @param  dist [Float] [A radius in miles]

 @return [Array] [Array of objects within dist of lat/long]