The following methods were reverted to expect a string containing the file name:
  Cnab240::Arquivo::Arquivo#save_to_file
  Cnab240::Arquivo::Arquivo.load_from_file

The new method was added to allow reading contents from an I/O interface:
  Cnab240::Arquivo::Arquivo.load
Cnab240::Builder#load_from_file renamed to Cnab240::Builder#load
Moved implementation common to all helper classes to a Cnab240::Helper class