audiowmark 0.6.3

Overview of Changes in audiowmark-0.6.3:

• update HLS support to build with ffmpeg-7 API (#68)
• preserve wav subformat (#64)
  • write float/double wav output for wav float/double input
  • write signed 16, 24 and 32 bit wav output for 16, 24, 32 bit wav input
  • added test that wav subformat format is preserved (make check)
• improved RawConverter:
  • support float/double input/output (very fast on little endian systems)
  • fix bug for unsigned integer raw input/output (16, 24 and 32 bit)
  • better tests (make check)
  • faster 16/32 bit conversion on little endian systems
• add format wav-pipe for very long input/output streams on stdin/stdout
• performance optimizations for SFOutputStream
• add documentation for Windows/Cygwin builds (#45)