Merge pull request myclabs#145 from MarkBaker/PHP8.1-Resolve-JsonSeri…

…alizable-Return-Datatype-Deprecation

Php8.1 resolve json serializable return datatype deprecation

Merge pull request myclabs#138 from Ocramius/feature/myclabs#134-mark…

…-__callStatic-as-pure

Fix myclabs#134 by marking `Enum::__callStatic` as `@psalm-pure`

Merge pull request myclabs#129 from iFixit/cache-instances

__callStatic: cache created Enum instances

Merge pull request myclabs#114 from iFixit/Psalm-seperate-annotations

Psalm: do not collide with doctrine templates

Merge pull request myclabs#112 from iFixit/clarify-psalm-types

Clarify psalm types

Move psalm to require-dev

Merge pull request myclabs#111 from jarstelfox/master

Add static type checking!

Merge pull request myclabs#97 from KartaviK/hotfix/enum-inheritance-c…

…ompatibility

 Solution for construct enum from inherited enum with incompatible value

Merge pull request myclabs#89 from jmsfwk/reduce-php-version

Change minimum PHP version to 7.1

Add return type declaration for "equals()" method (myclabs#88)

Add return type declaration for "equals()" method