def find_best_mime_type_match(q_value_header, available)
      find_best_q_match(q_value_header, available) do |a, b|
        match_mime_type?(a, b)
      end
    end
def find_best_mime_type_match(q_value_header, available)
      find_best_q_match(q_value_header, available) do |a, b|
        match_mime_type?(a, b)
      end
    end
Internal: Find the best qvalue match from an Array of available mime type
 options.

 Adapted from Rack::Utils#q_values.

 Returns the matched mime type String from available Array or nil.