0.3.0

version 0.3.0

Changes since 0.2.1:

• There is now an experimental, API-compatible C implementation of the
  Python blake3 module in the c_impl/ directory. This a
  proof-of-concept for code that might be submitted to Python's standard
  hashlib module in the future. It probably won't be published on PyPI.
• The multithreading keyword arg previously on blake3() and update()
  has been replaced with the max_threads keyword arg on blake3() only.
  This accepts any positive integer, or the special value blake3.AUTO,
  which is equivalent to the previous behavior. This change helps
  compatiblity with the current C implementation, which ignores
  max_threads, and with a hypothetical future C implementation, which
  might want to store a thread pool on the hasher.
• Added the reset() method. This is potentially helpful for reusing
  threading resources, which are currently local to the hasher when
  max_threads is greater than 1 and not equal to blake3.AUTO.
• Added a usedforsecurity keyword arg, for compatibility with hashlib.
  The value is currently ignored.
• Most keyword arguments are now strictly keyword-only, and data
  arguments are now strictly positional-only.