ONOS-542 Added ability for app bundle to carry it's own artifacts, including feature repo. Fixed onos-package script. Added JSON output to CLI.

Change-Id: If4f2c774d3fc2d68c0a8e91b3084b99d7c75d927
diff --git a/core/api/src/main/java/org/onosproject/app/ApplicationDescription.java b/core/api/src/main/java/org/onosproject/app/ApplicationDescription.java
index ec7958d..64f04a6 100644
--- a/core/api/src/main/java/org/onosproject/app/ApplicationDescription.java
+++ b/core/api/src/main/java/org/onosproject/app/ApplicationDescription.java
@@ -19,6 +19,7 @@
 import org.onosproject.core.Version;
 
 import java.net.URI;
+import java.util.List;
 import java.util.Optional;
 import java.util.Set;
 
@@ -71,10 +72,10 @@
     Optional<URI> featuresRepo();
 
     /**
-     * Returns the set of features comprising the application. At least one
+     * Returns the list of features comprising the application. At least one
      * feature must be given.
      *
      * @return application features
      */
-    Set<String> features();
+    List<String> features();
 }