VPP-57 Add missing license headers in doc files

Change-Id: Icd1f8952f66d3cee027c59f3148c67f1839de306
Signed-off-by: Chris Luke <chrisy@flirble.org>

svm/dir.dox

@@ -1,3 +1,19 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Copyright (c) 2016 Comcast Cable Communications Management, LLC.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 /* Doxygen directory documentation */
 /**
 @dir