Updated Notify_Custom_JSON (markdown)

Notify_Custom_JSON.md

@@ -10,7 +10,7 @@ The format might look something like this:
 ```json
 {
    "version": "1.0",
-   "title": "What A Great Movie Downloaded Successfully",
+   "title": "Some Great Software Downloaded Successfully",
    "message": "Plenty of details here",
    "type": "info"
 }
@@ -41,3 +41,23 @@ Send a JSON notification to our web server listening on port 80:
 # Assuming our {hostname} is json.server.local
 apprise json://json.server.local
 ```
+
+### Header Manipulation
+Some users may require special HTML headers to be present when they post their data to their server.  This can be accomplished by just sticking a hyphen (**-**) in front of any parameter you specify on your URL string.
+```bash
+# Below would set the header:
+#    X-Token: abcdefg
+#
+# Assuming our {hostname} is localhost
+# Assuming our {port} is 8080
+apprise "json://localhost:8080/path/?-X-Token=abcdefg"
+
+# Multiple headers just require more entries defined with a hyphen in front:
+# Below would set the headers:
+#    X-Token: abcdefg
+#    X-Apprise: is great
+#
+# Assuming our {hostname} is localhost
+# Assuming our {port} is 8080
+apprise "json://localhost:8080/path/?-X-Token=abcdefg&-X-Apprise=is%20great"
+```