In their infinite wisdom, the authors of the EIRENE FFFIS for GSM-R SIM
cards invented yet a new way of encoding data in SIM card files: The
first record of a file may be encoded differently than further records
of files.
Let's add the required infrastructure to pySim so that the encode and
decode methods for record-oriented files get passed in the current
record number.
Change-Id: I02d6942016dd0631b21d1fd301711c13cb27962b
Related: OS#5784