def parse_pref_string(arduino_output)
      lines = arduino_output.split("\n").select { |l| l.include? "=" }
      ret = lines.each_with_object({}) do |e, acc|
        parts = e.split("=", 2)
        acc[parts[0]] = parts[1]
        acc
      end
      ret
    end
def parse_pref_string(arduino_output)
      lines = arduino_output.split("\n").select { |l| l.include? "=" }
      ret = lines.each_with_object({}) do |e, acc|
        parts = e.split("=", 2)
        acc[parts[0]] = parts[1]
        acc
      end
      ret
    end
Convert a preferences dump into a flat hash
 @param arduino_output [String] The raw Arduino executable output
 @return [Hash] preferences as a hash