[WIP] Upgrade ONOS to karaf version 4.2.1

Change-Id: I7cd40c995bdf1c80f94b1895fb3344e32404c7fa
diff --git a/apps/yang/src/main/java/org/onosproject/yang/AbstractYangModelRegistrator.java b/apps/yang/src/main/java/org/onosproject/yang/AbstractYangModelRegistrator.java
index a068526..512d6d7 100644
--- a/apps/yang/src/main/java/org/onosproject/yang/AbstractYangModelRegistrator.java
+++ b/apps/yang/src/main/java/org/onosproject/yang/AbstractYangModelRegistrator.java
@@ -16,11 +16,11 @@
 
 package org.onosproject.yang;
 
-import org.apache.felix.scr.annotations.Activate;
-import org.apache.felix.scr.annotations.Component;
-import org.apache.felix.scr.annotations.Deactivate;
-import org.apache.felix.scr.annotations.Reference;
-import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.osgi.service.component.annotations.Activate;
+import org.osgi.service.component.annotations.Component;
+import org.osgi.service.component.annotations.Deactivate;
+import org.osgi.service.component.annotations.Reference;
+import org.osgi.service.component.annotations.ReferenceCardinality;
 import org.onosproject.yang.model.YangModel;
 import org.onosproject.yang.model.YangModuleId;
 import org.onosproject.yang.runtime.AppModuleInfo;
@@ -48,10 +48,10 @@
     protected YangModel model;
     private ModelRegistrationParam registrationParam;
 
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
     protected YangModelRegistry modelRegistry;
 
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
     protected YangClassLoaderRegistry sourceResolver;
 
     /**