Add reference to Google coding style in README

Issue: HIC-166
Change-Id: I478b686ddc4fdd3866e70f81009d18bcbd85175e
diff --git a/README.md b/README.md
index 8b61430..d9c48ed 100644
--- a/README.md
+++ b/README.md
@@ -131,6 +131,11 @@
 
 ## Development
 
+### Coding Style
+
+We follow the
+[Google Python Style Guide](https://github.com/google/styleguide/blob/gh-pages/pyguide.md).
+
 ### Setup
 
 We use tox to both test and validate the code quality: