Code modernizations for PHP 8.3

Fixes for PHP 8.1

Update psr/container compatibility

Allow support for psr/container both v1.1 and v2

Add "psr-11" as a tag in composer.json

v1.0.2

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 - Update requirements to allow [PHP 8.0](https://php.watch/versions/8.0)
 - Update to PHPUnit 9.3

v1.0.1

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Minor performance improvements.

v1.0.0

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Initial stable release.

v0.1.0

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