OPENNLP-1226: Training an NER model for dates with 'dd.mm.yyyy' as Date format

[mawiesne]

Change

• adds NameFinderMEWithDatesTest verifying German (and English) date formats, via custom training data per language, as reproducer for OpenNLP-1226
• adds RandomGermanNewsGenerator to generate synthetic news corpora with dates annotated, typical for DE locale
• adds RandomEnglishNewsGenerator to generate synthetic news corpora with dates annotated, typical for EN,US/UK/AUS locale
• extracts code to AbstractNameFinderTest to avoid cnp of re-usable code

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[mawiesne]

Will fix deprecation violation(s) after I had breakfast. 🙂