Adding leading zeros in chapters nubmers in output filenames when splitting by chapters

Fixed race condition during split sub-tracks and output by chapter

fixed issue of same job id was used for concatination of files during split by track, which created race conditions

Fixed playing mp3

#422 fixed

Tag Track

Fixed large file size estimate

Build 6.1

Track Tag in m4b and ogg files

Jpeg detection bug fixed

Year Tag fixed

Chapter naming fixes

support ArtWork from bin_data stream 

Better VBR for opus

Chapter edit - save custom title

Chapter naming - save as default

Filename format settings

Dark Mode and settings added

wav files support