Support for Memory classes in lz4-java #106

Druid is a open source datastore which uses Lz4-java for fast compression. We are moving our implementation from ByteBuffer to Memory . Memory provides the following benefits over ByteBuffer

• Faster reads/writes than ByteBuffer
• Allows us to address files/memory greater than 2GB
• Gets rid of endianess problems with ByteBuffers

I was thinking of adding an extra interface which woud decompress memory and has an interface like this:
decompress(Memory src, int srcOff, WritableMemory dest, int destOff, int destLen);

Would you be open to discussing such a change?

Cc: @leerho