Start testing admin-module

Convert to our wrapper class for assertions

* Upgrade saml2-library to v4

* Stop considering Issuer-strings

* Stop considering NameID-arrays

* Added Kernel class to handle request

* Kernel handle request

Kernel is loaded in SimpleSAML\Module class
Removed Router and ControllerResolver classes

* Added route command (squash)

* Use symfony application and cache

* Updated to today's standards

* Fix for Symfony4 & Catch environment from ENV variable

* Standardize location of routes/services files

* Trying to make slashes work properly in all situations

* Convert XML to YML

* Fix some template-names and endpoints

* Rename Controller-classes

* Update dependencies

* Fix routing files

* TooManyArguments

* Fix TypeCoercion

* PSR-12

* Fix rebase mistake

* Rebase lock-file

* Fix Psalm

* Add strict_types declaration

Co-authored-by: Sergio Gómez <decano@gmail.com>

* Raise minimum PHP version to 7.0

* Remove tests pre-PHP 7.2

* Upgrade dev dependencies

* Ignore tests for deprecated class

* Add typehints; not touching public API

* Remove none-array replacements-param; old behaviour from pre-1.4 release

* Psalm fixes

* Add upgrade notes

* PSR-12

PSR-12 compliancy

Fix Psalm-issues in the modules-directory