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- added short glossary
- updated docs to reflect naming changes
- rewritten usage
- renamed various object's usages and index_object to entity [thanks Michael Sweeney]
- renamed characteristics_value and value references to traits, as in Characteristic's trait. [thanks Michael Sweeney]
- renamed MatchBox.not_matching method into MatchBox.mismatch - signature remained the same.
- only None and empty list will be treated as a value not used for matching
- added repr method to box
- renamed exclude_unknown to mismatch_unknown to clarify set's meaning
- Extracted indexing logic from MatchBox to a base class.