update README.md

README.md

@@ -2,6 +2,7 @@
 Python utility that duplicates file modifications over the web via REST API, (or to a local directory) powered by [watchdog](https://github.com/gorakhargosh/watchdog).
 
 ## Usage
+You can run `restdog.py` as a standalone command-line tool:
 ```ps
 $python restdog.py [-h] [--api] [--interval INTERVAL] [--file_types FILE_TYPES [FILE_TYPES ...]] src_dir dest_dir
 
@@ -15,6 +16,14 @@ options:
   --interval            # update interval in seconds (default: 3600)
   --file_types          # whitespace-separated list of watched file types (default: "*.csv" "*.xls" "*.xlsx" "*.xlsm")
 ```
+Or install it into your local environment with `pip install restdog`, then invoke the CLI from another module with the `watch()` function:
+
+```py
+import restdog
+
+restdog.watch()
+```
+
 
 ## Example
 ```ps