* 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

* Bump to PHP 7.2

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

Closes: #1275

Broken during refactoring in 6607b7fb

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

In the modern template also clean up HTML a bit.

Add a common use case to add entity categories - until now it's
hard for users to find SSP examples for how to do it.

Different from the other options, setting it to null does not use
a default but throws an error if you enable metadata signing, so
enabling metadata signing in the default config will throw an
exception. Better to just leave it out, the option is documented
but should not be necessary for most installs, so needs not be
in the template.

We moved to Codecov

People might do this in the past to get correct metadata (thereby
breaking other email related functions). But our metadata generator
will now take care of this, so we can just ignore any mailto: prefix.

The testsuite already confirms this behaviour.

After logout, you would be redirected to a non-existent path (404).
Likely the best place to be redirected after logout is the base.