Release v1.0.0

Added

• The storage backends do have now a method query_documents() to leverage economies of scale when
  querying multiple documents at once.

Changed

• The public interface of the library is declared stable, hence it is ready for version 1.0.
• char_ngrams() is now fully implemented in Rust, giving a speedup of 2x.
• minhash LSH uses the new query_documents() of the storage backends instead of running concurrent
  queries.

Fixed

• Wrong operator precedence in minhash implementation, which lead to incorrect results.
• Incorrect parsing of tokenize argument for SimilarityStore for char_ngrams without padding.