Support Compression / Decompression with Dictionaries

[felixhandte]

The current LZ4 C lib supports priming the codec state with a dictionary (in a newer, nicer way). It would be nice to surface those features in this library.

I'm looking at adding this now.

[iSynaptic]

Has anyone made progress on this?

[wsargent]

The frame format has the option of using a dictionary id, but there is no setting for it in the FLG structure https://github.com/lz4/lz4-java/blob/master/src/java/net/jpountz/lz4/LZ4FrameOutputStream.java#L320

I can do this with zstd-jni and -5 debug level so that's good enough.