ref-manual: Added the license class.

(From yocto-docs rev: 6958ed69a82bef1305cd3c4d5257dc412254348b)

Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/ref-manual/ref-classes.xml

@@ -1042,6 +1042,15 @@
     </para>
 </section>
 
+<section id='ref-classes-license'>
+    <title><filename>license.bbclass</filename></title>
+
+    <para>
+        The license (<filename>license</filename>) class provides license
+        manifest creation and license exclusion.
+    </para>
+</section>
+
 <section id='ref-classes-mime'>
     <title><filename>mime.bbclass</filename></title>