cfg pickle files of older Version cause a crash of more recent MSS under windows only

[Joern Ungermann]

It seems as if some of the stored settings pickle file may still crash a newer MSS. The desired behaviour in this case should be a simple warning and a discarding of the stored settings and return to defaults. The settings shall then be overwritten with the default settings.

[Joern Ungermann]

See here:

https://stackoverflow.com/questions/1746825/python-valueerror-insecure-string-pickle

It most likely stems from our change of "r"/"w" to "rb"/"wb", which causes a difference on Windows and should enable interpoperatbility of files between OS versions.

[Reimar Bauer]

Unpickling can cause a ValueError for pickles stored with older versions of MSS

The Issue seems to be relevant under Windows only, where we (correctly!) changed the "w"/"r" to "wb"/"rb".

Fix issue #284

→ <<cset a824756dbeb7>>