Fix copyright notices

- Add missing copright header in conf.py.
- Fix inconsistent copyright notice line breaking.

Change-Id: Ib78f7768643069c49ff986a48a176df9fd06e891
diff --git a/docs/style_guide.rst b/docs/style_guide.rst
index b8cabd9..6254d0f 100644
--- a/docs/style_guide.rst
+++ b/docs/style_guide.rst
@@ -205,16 +205,16 @@
   // Copyright 2019 The Pigweed Authors
   //
   // 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
+  // use this file except in compliance with the License. You may obtain a copy of
+  // the License at
   //
   //     https://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.
+  // License for the specific language governing permissions and limitations under
+  // the License.
   #pragma once
 
   // Header file-level comment goes here...