Update README: new C++ extractor link

Author: urialon

README.md

@@ -180,6 +180,8 @@ A "released" model usually takes ~3x less disk space.
 
 This project currently supports Java and C\# as the input languages.
 
+_**March 2020** - a code2seq extractor for **C++** based on LLVM was developed by [@Kolkir](https://github.com/Kolkir/) and is available here: [https://github.com/Kolkir/cppminer](https://github.com/Kolkir/cppminer). 
+
 _**January 2020** - a code2seq extractor for Python (specifically targeting the Python150k dataset) was contributed by [@stasbel](https://github.com/stasbel). See: [https://github.com/tech-srl/code2seq/tree/master/Python150kExtractor](https://github.com/tech-srl/code2seq/tree/master/Python150kExtractor)._
 
 _**January 2020** - an extractor for predicting TypeScript type annotations for JavaScript input using code2vec was developed by [@izosak](https://github.com/izosak) and Noa Cohen, and is available here: