Update README.md

Author: bennettgoble

README.md

@@ -1,4 +1,23 @@
 # Linden Lab Base
 
+[![codecov](https://codecov.io/gh/secondlife/python-llbase/branch/main/graph/badge.svg?token=GUB4VX1OSG)](https://codecov.io/gh/secondlife/python-llbase)
+
 Vintage python utility modules used by Linden Lab, the creators of
 [Second Life](https://secondlife.com).
+
+## Use
+
+Install llbase:
+
+```
+pip install llbase
+```
+
+Use it:
+```py
+from llbase.config import Config
+
+config = Config("./config.xml")
+
+print(config.get("my-setting"))
+```