Fix flash of descriptive text before recent cats shown

Switch from hiding the "skip" text after looking up cats,
to hiding it initially and showing it after doing the local
search for recent cats.

commons/res/layout/fragment_categorization.xml

@@ -51,6 +51,7 @@
         android:gravity="center"
         android:focusable="true"
         android:text="@string/categories_skip_explanation"
+        android:visibility="gone"
         />
 
     <ListView