A best effort fla parser.
- Newer FLAs appear to be zips. Work will focus there.
- https://stackoverflow.com/questions/1494617/is-there-an-unofficial-flash-fla-spec
- https://fileinfo.com/extension/fla
- https://stackoverflow.com/questions/4077200/whats-the-meaning-of-the-non-numerical-values-in-the-xfls-edge-definition
- https://en.wikipedia.org/wiki/SWF#Related_file_formats_and_extensions