class library: Scale/Tuning - whitespace cleanup

Signed-off-by: Tim Blechmann <tim@klingt.org>
class library: Scale - cleanups

* fix default constructor
* avoid checkTuningForMismatch method

Signed-off-by: Tim Blechmann <tim@klingt.org>
class library: Tuning - *et should use predefined et tunings

Signed-off-by: Tim Blechmann <tim@klingt.org>
class library: Scale/Tuning - fix serialization

* findKeyForValue used in storedKey won't work with parent events, so we
  cannot find the key ...
* even if it worked, there is no guarantee that this specific key is
  actually part of the dictionary (e.g. when adding a custom scale/tuning
  at run-time)

Signed-off-by: Tim Blechmann <tim@klingt.org>
class library: Tuning - noteToFreq now supports fractional notes

Signed-off-by: Tim Blechmann <tim@klingt.org>
class library: scale - fix degreeToNote for accidentals

Signed-off-by: Tim Blechmann <tim@klingt.org>