reading anything prior stopped working some time ago, let's not kid ourselves.
nobody needs to read those datafiles, they are more than 7 years old.
less code is better.
if access to these files is needed, check out an old version from source control.
this should make future debugging sessions easier, telling us what bugs were or were not fixed at the time of an incident.
added a test to make sure data file can be read/written, and at a minimum, sets global data-version.
also clean up test framework a bit, and introduce a helpful macro.