Merge branch '5.1'

Merge branch '5.0' into 5.1

Re-add return type hint that was lost during upmerges

Re-adds the `void` return type for `EmailFinisher::addMessages()`

Merge pull request from GHSA-m5vx-8chx-qvmm

BUGFIX: Don't skip validators for GET requests

Merge pull request #133 from neos/bugfix/formviewhelper-fragment

BUGFIX: Set uri section in form viewhelper

Merge branch '5.0' into 5.1

Merge pull request #127 from dlubitz/patch-1

BUGFIX: Allow DateTime for unserialization of form state

Merge pull request #125 from DrillSergeant/patch-1

BUGFIX: Remove void return type to stay compabible with PHP 7.0

Merge pull request #123 from neos/analysis-J2xjrW

TASK: Apply fixes from StyleCI

Merge pull request #120 from kdambekalns/bugfix/getuploadedimage-retu…

…rn-type

BUGFIX: Allow ImageInterface to be returned in UploadedImageViewHelper