add version tag to documentation

.travis.yml

@@ -61,6 +61,7 @@ matrix:
       install:
         - npm install -g vuepress
       script:
+        - sed -i 's/version_tag/'$TRAVIS_TAG'/g' docs/.vuepress/config.js
         - npm run docs:build
       before_deploy: echo "docs.openmqttgateway.com" >> docs/.vuepress/dist/CNAME
       deploy:

docs/.vuepress/config.js

@@ -2,7 +2,7 @@ module.exports = {
     markdown: {
       lineNumbers: true
     },
-    title: 'OpenMQTTGateway',
+    title: 'OpenMQTTGateway version_tag',
     description: 'One gateway, many technologies: MQTT gateway for ESP8266, ESP32, Sonoff RF Bridge or Arduino with bidirectional 433mhz/315mhz/868mhz, Infrared communications, BLE, beacons detection, mi flora / mi jia / LYWSD02/ Mi Scale compatibility, SMS & LORA.',
     head: [
       ['link', { rel: "icon", type: "image/png", sizes: "32x32", href: "/img/favicon-32x32.png"}],