Allow PHP 8, drop Symfony integration

See #14 and #15

Add support for Broadway 2

See #11.

Add option to hydrate using closures

See #9, thanks @haampie.

Allow for (de)serialization of objects with no properties

See #8.

Performance testing and PHP compatibility

See #5 and #6.

Fix readme and make compatible with Symfony 3.0

Merge pull request #2 from MarkRedeman/patch-1

Fix incorrect use case statement in readme