Update label.adoc

Turned note text into Admonition.

src/docs/asciidoc/jme3/contributions/tonegodgui/label.adoc

@@ -12,8 +12,10 @@ Though there was no real need for providing a Label class, as the Element class
 *  1. Provide the 3 common constructors
 *  2. Use of styles to allow for global settings for all text using the Label class.
 
-NOTE:
+[NOTE]
+====
 Style information can be overridden by any instance by using the Text/Font setters provided by the Element class
+====
 
 '''