Java API for TableFactory should follow C++ API

At the moment the Java API has the notion of sub-classes of `TableFormatConfig` (e.g. `PlainTableFormatConfig`) which combine both the C++ options for a specific type of `TableFactory`, and a reference to the `TableFactory`. I think the Java API should be refactored here to follow the C++ API more closely to avoid confusion.

When examining https://github.com/facebook/rocksdb/issues/5297 I found the divergence between the C++ and Java APIs to make understanding the issue and debugging more complex.