Reference to author implementation

Found on the first author's website: http://urialon.cswp.cs.technion.ac.il/publications/

Signed-off-by: Helge Spieker <helge@simula.no>

Author: HelgeS

README.md

@@ -1,2 +1,5 @@
 # code2vec
 MLonCode community effort to implement Learning Distributed Representations of Code (https://arxiv.org/pdf/1803.09473.pdf)
+
+Note: The authors of the paper have released their own tensorflow implementation on [GitHub](https://github.com/tech-srl/code2vec).
+[Token vectors](https://s3.amazonaws.com/code2vec/model/token_vecs.tar.gz) and [Method name vectors](https://s3.amazonaws.com/code2vec/model/target_vecs.tar.gz) for their paper are available as well.