code: public JsonObject add(String name, int value) {
      add(name, Json.value(value));
      return this;
    }
docs: Appends a new member to the end of this object, with the specified name and the JSON
  representation of the specified <code>int</code> value.
  <p>
  This method <strong>does not prevent duplicate names</strong>. Calling this method with a name
  that already exists in the object will append another member with the same name. In order to
  replace existing members, use the method <code>set(name, value)</code> instead. However,
  <strong> <em>add</em> is much faster than <em>set</em></strong> (because it does not need to
  search for existing members). Therefore <em>add</em> should be preferred when constructing new
  objects.
  </p>
  
  @param name
  the name of the member to add
  @param value
  the value of the member to add
  @return the object itself, to enable method chaining