update readme

Author: ashikov

README.md

@@ -21,6 +21,10 @@ pip install hexlet-pairs
     pairs.cdr(p)  # 'foo'
     print(pairs.to_string(p))  # cons(42, 'foo')
 
+---
+
 [![Hexlet Ltd. logo](https://raw.githubusercontent.com/Hexlet/assets/master/images/hexlet_logo128.png)](https://ru.hexlet.io/pages/about)
 
 This repository is created and maintained by the team and the community of Hexlet, an educational project. [Read more about Hexlet (in Russian)](https://ru.hexlet.io/pages/about?utm_source=github&utm_medium=link&utm_campaign=python-pairs).
+
+See most active contributors on [hexlet-friends](https://friends.hexlet.io/).