respond with BUILD FAILED on exception

git-svn-id: https://svn.apache.org/repos/asf/maven/components/trunk@162988 13f79535-47bb-0310-9956-ffa450edef68

maven-core/src/main/java/org/apache/maven/DefaultMaven.java

@@ -142,6 +142,9 @@ public class DefaultMaven
 
                     line();
                 }
+
+                // An exception is a failure
+                return response;
             }
         }