Convert to string before replace (#186)

This fixes this error  text.replace is not a function
When somebody has this nickname 1234567890 it thorws error in the server viewer.

src/js/script.js

@@ -124,7 +124,7 @@ function escapeHtml(text) {
         "'": '''
     };
 
-    return text.replace(/[&<>"']/g, function(m) { return map[m]; });
+    return text.toString().replace(/[&<>"']/g, function(m) { return map[m]; });
 }
 
 function updateTooltip(el, text) {