Add support [readonly] modifier to lua docs

luacs-docs/lua/css/ldoc.css

@@ -544,6 +544,9 @@ a.reference {
   background-color: rgb(115, 53, 142);
 }
 
+.tag.readonly {
+  background-color: rgb(47, 100, 74);
+}
 
 .tag.type {
   background-color: rgb(31, 141, 155);

luacs-docs/lua/templates/module.ltp

@@ -71,6 +71,7 @@
               {% local displayName = item:display_name_of(argumentName) %}
               {% local type = ldoc.typename(item:type_of_param(argumentName)) %}
               {% local default = item:default_of_param(argumentName) %}
+              {% local readonly = item:readonly(argumentName) %}
 
               <li>
                 <span class="tag parameter">{{displayName}}</span>
@@ -85,6 +86,10 @@
                   <span class="tag default">optional</span>
                 {% end %}
 
+                {% if (readonly) then %}
+                  <span class="tag readonly">read-only</span>
+                {% end %}
+
                 <p>{* ldoc.markup(item.params.map[argumentName]) *}</p>
               </li>
             {% end %}