This release introduces support for PHP 7.1 functionality, specifically:

• nullable parameter and return types
• void hint support
• iterable hint support

In addition to that, performance improvements were introduced in the FileDriver, and minor cleanups were performed all over the codebase.

Total issues resolved: 11

• 394: Improve FileDriver Mapping data retrieval by caching results locally
• 706: Travis-CI: drop PHP 7.0 from allowed failures, it passes well
• 719: Improve the phpdoc of ObjectRepository
• 720: Fixed detection of identifier getter with PHP 7 return type
• 721: Small improvements from humbug mutation testing discoveries
• 724: Upgrade PHPUnit and PHP version dependencies
• 725: Removing useless incremental of the current exporting level from debug exporter
• 729: Util\Debug: export parent class private attributes and DateTimeImmutable
• 731: Support nullable types (PHP 7.1) in ProxyGenerator
• 734: ProxyGenerator: Added support for PHP 7.1 features
• 743: Fix parameter/return type validation for interfaces (introduced in #734)