Fix Locale; If a Twig-variable is not set and then translated, these methods are called with a null parameter

* Remove deprecated classes

* Remove support for certificate fingerprints

* Remove many deprecated methods and pieces of code

* Remove SAML1.1/Shib1.3 support

* Remove many superfluous annotations

* Update unit test to work with new PHPunit

Closes #1268 
Closes #1020 
Closes #431 
Closes #167 
Closes #151 

* Migrate assertions to Webmozart

* Upgrade saml2-library to v4

* Stop considering Issuer-strings

* Stop considering NameID-arrays

This makes it mirror how it used to work and how the twig templates
work. The solution is not pretty, but the longer term solution is to
just get rid of the oldui exception.

Also actually run the existing EMail unit tests. That might have
caught this.

Closes: #1269

Broken during refactoring in 6607b7fb

Non-file-upload crashed on Symfony request building.
File upload crashed because of not using the actual path.