5.7.0

• Performance improvement to use less the nextToken() function (#397) by @iifawzi
• Lexer - Solving ambiguity on function keywords (#385) by @iifawzi
• Implement ALTER EVENT (#404) by @iifawzi
• Add ALTER EVENT keywords (#404) by @iifawzi
• Drop PHP 7.1 support by @williamdes
• Fix the alter operation table options RENAME INDEX x TO y (#405) by @iifawzi
• Fix CreateStatement function's options (#406) by @iifawzi
• Fix a PHP notice on Linter using ANALYZE (#413) by @iifawzi