v2.5.1

Version 2.5.1 (2021-09-02)

• Import ftfy and use its uncurl_quotes method to turn curly quotes into
  straight ones, providing consistency with multiple forms of apostrophes.

• Set minimum version requierements on regex, jieba, and langcodes
  so that tokenization will give consistent results.

• Work around an inconsistency in the msgpack API around
  strict_map_key=False.

Version 2.5 (2021-04-15)

• Incorporate data from the OSCAR corpus.