implement api level toggling
 and rename navtree.js to android-developer-reference.js for all reference related scripts
 TODO: shading for hidden classes in the treeview navigation... these aren't dynamic yet.
diff --git a/tools/droiddoc/src/ClassInfo.java b/tools/droiddoc/src/ClassInfo.java
index 0941595..8180436 100644
--- a/tools/droiddoc/src/ClassInfo.java
+++ b/tools/droiddoc/src/ClassInfo.java
@@ -863,6 +863,7 @@
         data.setValue(base + ".kind", this.kind());
         TagInfo.makeHDF(data, base + ".shortDescr", this.firstSentenceTags());
         TagInfo.makeHDF(data, base + ".deprecated", deprecatedTags());
+        data.setValue(base + ".since", getSince());
     }
 
     /**