added options to readme

README.md

@@ -7,7 +7,24 @@ Python Interpreter Executing Remotely
 Run in a terminal:
 
 ```bash
-./pier.py
+$ ./pier.py
 ```
 
 Open in a browser: http://localhost:9090/
+
+## Options
+
+```bash
+$ ./pier.py -h
+usage: pier.py [-h] [-d DIR] [-H HOST] [-P PORT]
+
+pier - Python Interpreter Executing Remotely
+
+optional arguments:
+  -h, --help            show this help message and exit
+  -d DIR, --dir DIR     directory containing python scripts (default: ./scripts/)
+  -H HOST, --host HOST  host name (default: localhost)
+  -P PORT, --port PORT  port number (default: 9090)
+
+```
+