add link to source code in navigation bar

launch.html

@@ -547,6 +547,9 @@
       <a class="button secondary" href="https://www.bnvb-ingenieure.de/impressum" target="_blank" rel="noopener noreferrer" data-i18n="impressum">
         Impressum
       </a>
+      <a class="button secondary" href="https://git.bnvb.eu/stefan.tollkuehn/jitsi-launch" target="_blank" rel="noopener noreferrer" data-i18n="source">
+        Source
+      </a>
       <div id="langMenu" class="lang-menu">
         <button id="langButton" class="button secondary" type="button" aria-haspopup="true" aria-expanded="false">
           <img id="langFlag" class="lang-flag" src="assets/uk.svg" alt="">
@@ -842,6 +845,7 @@
         en: {
           pageTitle: "Jitsi Meeting",
           impressum: "Legal Notice",
+          source: "Source",
 
           launcher: {
             title: "Jitsi Meeting",
@@ -934,6 +938,7 @@
         de: {
           pageTitle: "Jitsi Meeting öffnen",
           impressum: "Impressum",
+          source: "Quellcode",
 
           launcher: {
             title: "Jitsi Meeting",
@@ -1028,6 +1033,7 @@
         fr: {
           pageTitle: "Réunion Jitsi",
           impressum: "Mentions légales",
+          source: "Code source",
 
           launcher: {
             title: "Réunion Jitsi",
@@ -1121,6 +1127,7 @@
         zh: {
           pageTitle: "Jitsi 会议",
           impressum: "法律声明",
+          source: "源代码",
 
           launcher: {
             title: "Jitsi 会议",