Allow integrator to limit results in widget to certain languages.
If only one language is allowed, labels will be translated.
Otherwise default system language is used.
E.g. one record will be displayed in multiple languages, it would be
confusing to show him multiple times for each language.
Add TYPO3 extension for phpstan as many things would break within tests.
Relates: #15
Allow Integrator to define rules to track views of records.
This allows to add tracking to extensions like tx_news.
Integrators are able to define matching rules on current request. If a
request matches, the record is stored as individual view beside existing
pageview.
Relates: #14
