Implemented LZF compression codec

Motivation:

LZF compression codec provides sending and receiving data encoded by very fast LZF algorithm.

Modifications:

- Added Compress-LZF library which implements LZF algorithm
- Implemented LzfEncoder which extends MessageToByteEncoder and provides compression of outgoing messages
- Added tests to verify the LzfEncoder and how it can compress data for the next uncompression using the original library
- Implemented LzfDecoder which extends ByteToMessageDecoder and provides uncompression of incoming messages
- Added tests to verify the LzfDecoder and how it can uncompress data after compression using the original library
- Added integration tests for LzfEncoder/Decoder

Result:

Full LZF compression codec which can compress/uncompress data using LZF algorithm.

See also issue #81