readme: added configuration & usage section

README.md

@@ -4,3 +4,30 @@ automates toontown rewritten's login process
 ## Installation
 
     $ pip3 install --user --upgrade tooncher
+
+## Configuration
+
+```yaml
+# default path: $HOME/.tooncher
+accounts:
+- username: toon
+  password: secret
+- username: ceo
+  password: golf
+- username: cfo
+  password: train
+engine_path: '/opt/Toontown Rewritten/TTREngine'
+```
+
+## Usage
+
+```
+$ tooncher [username]
+```
+
+### Examples
+
+```
+$ tooncher toon
+$ tooncher ceo
+```