add: zabbix signal notify script

zabbix-signal-webhook-script.js

@@ -0,0 +1,25 @@
+try {
+
+    var params = JSON.parse(value);
+    Zabbix.log(4, '[ Signal Webhook ] Executed with params: ' + params.URL + ', ' + params.Message);
+
+    if (!params.URL) {
+        throw 'Cannot get url';
+    }
+
+    fields = { 
+        message : params.Message,
+        number : params.number
+    }
+
+    var req = new HttpRequest();
+    req.addHeader('Content-Type: application/json');
+
+    var resp = req.post(params.URL, JSON.stringify(fields))
+    return 'OK';
+
+}
+catch (error) {
+    Zabbix.log(3, '[ Signal Webhook ] ERROR: ' + error);
+    throw 'Sending Signal Message failed: ' + error;
+}