Tools can be selected through URL (solves #161) (#207)

Co-authored-by: Adam Bem <adam.bem@zoho.eu>
Reviewed-on: #207
Reviewed-by: Mikolaj Widla <widlam@noreply.example.com>

Frontend/assets/scripts/frame.js

@@ -30,7 +30,14 @@ function init() {
     tools.set("mock", "tools/mock.html");
 
     changeActiveTools('XML');
+    var toolUrl = window.location.search.substring(1);
+    if (toolUrl == "")
         loadLastPage();
+    else if (tools.has(toolUrl))
+        changeTool(toolUrl);
+    else
+        loadLastPage();
+    
 }
 
 /**
@@ -81,6 +88,7 @@ function changeTool(tool) {
     const url = tools.get(tool);
     localStorage.setItem("lastPage", tool);
     document.getElementById("iframe").src = url;
+    document.location.search = tool;
 }
 
 /**