Overview of changes:

 *  (Almost) finish porting to JAT

    The test body was not fully rewritten; now it is (we still need
    to fill in RPM gap)

 *  Fixed typo in api/mseverity

Known issues:

 *  api/nativity is missing special rpms
    https://github.com/AloisMahdal/jats-preupgrade-assistant/issues/1

The test body was not properly rewritten.  What still remains, though,
is that we don't have replacement for special RPMs.

Overview of changes:

 *  Fixed typo in function name

Overview of changes:

 *  Migrated preupg/in-pipe from downstream

 *  Various README fixes