Fixing javadoc groupings.

Change-Id: If35e06fb3889fd9895b3d3d1a1bf44740865dea8
diff --git a/docs/internal-stores b/docs/internal-stores
index 13c0043..1f1f05a 100644
--- a/docs/internal-stores
+++ b/docs/internal-stores
@@ -1 +1,2 @@
 org.onosproject.store.*
+org.onosproject.persistence.impl