Allow StandardErrorLoggingHandler to be used

cURL is not strictly required, as checking for updates is done only if the configuration allows it. This commit fixes also a misspelling error (s/suggests/suggest/) and adds the rest of optional dependencies as suggestions.

Basic unit tests for metarefresh module

Use of fingerprints is deprecated elsewhere in the code, so we should
assume that to be the case here. Improves coverage in any event.

Make metarefresh work in 1.17.0 rc1

Fixed typo introduced by #1008

Fixes a typo introduced by #906

* Autoloader infinite recursion fix

Fixes simplesamlphp/simplesamlphp#1030

* Added test to ensure old autoloader behaviour is preserved

Also fixed undefined variable notice

Added Slovenian remember translations

Added slovenian processing translation

added slovenian consent abort translation

* Update simplesamlphp-theming.md

* Add theme.controller config setting

class_implements() returns class names without leading backslash

Items in $warnings should either be a string or an array with two values

* Correct xh translations issue #1022