v0.2.0

Changelog

• e800b33 add benchmark and avoid recomputing distance for ranges
• 48ae792 add documentation about composite index/uniques
• a7ab949 benchmark for large rows
• a76dd08 complete refactoring of api and imporve recursive performance
• b90754b remove old files
• 543e8be rename recursive to recursion
• f7bd17b update readme to reflect refactor
• 620cf24 wip refactored