v1.3.0

• Moved development to OHF-Voice org
• Removed C++ code for now to focus on Python development
  • A C API libpiper written in C++ is planned
• Embed espeak-ng directly instead of using separate piper-phonemize library
• Change license to GPLv3
• Use Python stable ABI (3.9+) so only a single wheel per platform is needed
• Change Python API:
  • PiperVoice.synthesize takes a SynthesisConfig and generates AudioChunk objects
  • PiperVoice.synthesize_raw is removed
• Add seperate piper.download_voices utility for downloading voices from HuggingFace
• Allow text as CLI argument: piper ... -- "Text to speak"
• Allow text from one or more files with --input-file <FILE>
• Excluding any file output arguments will play audio directly with ffplay
• Support for raw phonemes in text with [[ <phonemes> ]]
• Adjust output volume with --volume <MULTIPLIER> (default is 1.0)