began implementing MastershipManager

Change-Id: I65b86dcfa062e4cfd74de588f4714b35e9d329f0
diff --git a/core/api/src/main/java/org/onlab/onos/cluster/MastershipProvider.java b/core/api/src/main/java/org/onlab/onos/cluster/MastershipProvider.java
new file mode 100644
index 0000000..2cbad7f
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/cluster/MastershipProvider.java
@@ -0,0 +1,7 @@
+package org.onlab.onos.cluster;
+
+import org.onlab.onos.net.provider.Provider;
+
+public interface MastershipProvider extends Provider {
+
+}