The config now does "deep assignments"
See https://github.com/MetaModels/core/issues/193
Bugfix: MetaModelFilterRuleTags:getMatchingIds() does not crash anymore when the sanitized value
has no results.
Merge branch 'dev' of git://github.com/MetaModels/attribute_tags into contao3
First iteration of Contao 3 compat with namespaces.