TODO:
- Read/Write ID3v2.4 tag footer
- Implement ID3v2.3 Builder
- Implement more known frames currently read as UNKNOWN
MAYBE:
- Writing with unsynchronised data
- Simplify more rare complex frames (e.g. RVA/RVA2/GEOB, ...)
- Support for ID3v1 variants (Extended tag TAG+, APE, CUSTOMTAG)
- Implement known PRIV Tags (e.g. AverageLevel, WM_MediaClassPrimaryID, ...)