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

Merge pull request myclabs#84 from KartaviK/hotfix/ext-json-requirements

 Add ext-json to requirements for package

Merge pull request myclabs#83 from KartaviK/feature/envelope-enum-con…

…struct

 Create instance of enum from same enum in constructor

Merge pull request myclabs#82 from myclabs/fix-coding-style

Fix coding style