Add Codacy badge (#33)

Author: codacy-badger

README.md

@@ -1,5 +1,7 @@
 # phpypam: Python API client library for phpIPAM installation
 
+[![Codacy Badge](https://api.codacy.com/project/badge/Grade/6b89ed13b6694197944cddea94c953ed)](https://app.codacy.com/gh/codeaffen/phpypam?utm_source=github.com&utm_medium=referral&utm_content=codeaffen/phpypam&utm_campaign=Badge_Grade_Settings)
+
 phpypam is intended to be a complete library for speaking with phpIPAM API.
 
 Using `phpypam` is as easy as using the UI.