Change to html5 (#958)

* Change to html5

with Nu Html Checker

* Update scale-pages.html

* Update sign.html

* Update common.html

* Update common.html

* Update login.html

src/main/resources/templates/fragments/errorBanner.html

@@ -35,8 +35,8 @@
     function copytrace() {
       var flip = false
       if(!traceVisible) {
-         toggletrace()
-         flip = true
+        toggletrace()
+        flip = true
       }
       var traceContent = document.getElementById("traceContent");
       var range = document.createRange();