js: Convert space after tick in menus to a space character

Older Firefox versions don't support "-moz-appearance: none" on radio
buttons, which seems to mean that the specifies padding for them
doesn't appear.  Using a space character instead works fine, so do that
everywhere.  This seems to move the text slightly closer to the tick on
browsers that do support "appearance: none", but the result is quite
acceptable.

This also makes the focus outline on the ticks slightly less weird.

emcclib.js

@@ -83,7 +83,7 @@ mergeInto(LibraryManager.library, {
         tick.name = "preset";
         tick.value = value;
         label.appendChild(tick);
-        label.appendChild(document.createTextNode(name));
+        label.appendChild(document.createTextNode(" " + name));
         item.appendChild(label);
         gametypesubmenus[menuid].appendChild(item);