Adjust readme

Author: bcb

README.md

@@ -11,6 +11,7 @@
 
 Process incoming JSON-RPC requests in Python.
 
+To serve JSON-RPC requests:
 ```python
 from jsonrpcserver import Success, method, serve
 
@@ -22,6 +23,13 @@ if __name__ == "__main__":
  serve()
 ```
 
+Or use `dispatch`:
+```python
+>>> from jsonrpcserver import dispatch
+>>> dispatch('{"jsonrpc": "2.0", "method": "ping", "id": 1}')
+'{"jsonrpc": "2.0", "result": "pong", "id": 1}'
+```
+
 Full documentation is at [jsonrpcserver.com](https://www.jsonrpcserver.com/).
 
 See also: [jsonrpcclient](https://github.com/explodinglabs/jsonrpcclient)