Zebra ZPL

Generate a ZPL string from a hash.

Example of the desired usage:

label = ZebraZpl::Label.build do

  orientation   :n
  home          [20, 0]
  default_width 0, 0
  print_rate    :a
  quantity      4

  field [5, 20] do
    font  :d, height: 60
    width 1175
    lines 5
    data  'Test'
  end

end

label.to_s # => ^XA^FWN^LH20,0^BY0,0^PRA^PQ4^FO5,20^ADN,60^FB1175,5,,^FDTest^FS^XZ