It adds CsvRowSerializationSchema, CsvRowDeserializationSchema, a new CSV descriptor,
CsvRowTableFormatFactory, documentation and tests

The format integrates nicely with most SQL types.

It deprecates the "old CSV" descriptor stack and prepares also for FLINK-7050 (#4660).

The old CSV descriptor is still available under as "OldCsv".

This closes #7777.