Version 2.2.1 released -- Minor, but important fixes

Hello again! This time, we've made some more minor changes to AudioButcher, but we still added a few more features.

New features:

•  Added "start onsets" and start onset files -- they kind of work like average start times, but for onset files; (Keep in mind that just like start times, they are optional)
• Added the ability to import MP3 files without the need of FFmpeg*;

*Installing FFmpeg is still recommended though, as importing MP3 files is faster that way + more audio formats are supported;

Bugfixes:

• The "Minimum fade backmask" parameter now works as intended;
• Got rid of the long pause between scrambling and previewing;
• The lognormal distribution mode is no longer affected by the time measure mode;
• The folded normal mode is now affected by the time measure mode instead;

Merry (late) Christmas and happy scrambling!