Improved README.md documentation

README.md

@@ -168,6 +168,13 @@ curl -X POST -d 'urls=mailto://user:[email protected]' \
 curl -X POST -d '{"urls": "mailto://user:[email protected]", "body":"test message"}' \
     -H "Content-Type: application/json" \
     http://localhost:8000/notify
+
+# attach= is an alias of attachment=
+# Send a notification with a URL based attachment
+curl -X POST \
+    -F 'urls=mailto://user:[email protected]' \
+    -F attach=attach=https://raw.githubusercontent.com/caronc/apprise/master/apprise/assets/themes/default/apprise-logo.png \
+    http://localhost:8000/notify
 ```
 
 You can also send notifications that are URLs.  Apprise will download the item so that it can send it along to all end points that should be notified about it.
@@ -252,6 +259,13 @@ curl -X POST \
     -F [email protected] \
     -F attach2=@/my/path/to/Apprise.doc \
     http://localhost:8000/notify/abc123
+
+# attach= is an alias of attachment=
+# Send a notification with a URL based attachment
+curl -X POST \
+    -F 'urls=mailto://user:[email protected]' \
+    -F attach=attach=https://raw.githubusercontent.com/caronc/apprise/master/apprise/assets/themes/default/apprise-logo.png \
+    http://localhost:8000/notify/abc123
 ```
 
 🏷️ You can also leverage *tagging* which allows you to associate one or more tags with your Apprise URLs.  By doing this, notifications only need to be referred to by their easy to remember notify tag name such as `devops`, `admin`, `family`, etc. You can very easily group more than one notification service under the same *tag* allowing you to notify a group of services at once.  This is accomplished through configuration files ([documented here](https://github.com/caronc/apprise/wiki/config)) that can be saved to the persistent storage previously associated with a `{KEY}`.