Update to 2.0.1-RC8
-------------------
Since -RC7 was released, two serious problems were reported, which are now corrected in the
-RC8 release.

TQSL did not limit the number of copies of TQSL that can run at the same time. If two copies
of TQSL are running at the same time signing logs, this would result in corrupting the
database that keeps track of processed QSOs.

The QSO database used a storage format that could result in significant performance
degradation when a larg number of QSOs and/or logs were processed, eventually running out of
database resources for very large logs. RC8 will transparently update the QSO database to a
more appropriate format which does not suffer from this performance wall.
Clang to use libc++ for atomic.