Formalized HostStore in preparation for separating managers and stores.
diff --git a/core/trivial/src/main/java/org/onlab/onos/net/trivial/device/impl/SimpleDeviceStore.java b/core/trivial/src/main/java/org/onlab/onos/net/trivial/device/impl/SimpleDeviceStore.java
index 3fa9dc2..30c506ff 100644
--- a/core/trivial/src/main/java/org/onlab/onos/net/trivial/device/impl/SimpleDeviceStore.java
+++ b/core/trivial/src/main/java/org/onlab/onos/net/trivial/device/impl/SimpleDeviceStore.java
@@ -60,6 +60,7 @@
     public void deactivate() {
         log.info("Stopped");
     }
+
     @Override
     public int getDeviceCount() {
         return devices.size();