Run clang-format on the entire repo

This patch clang-formats the entire repo. Third-party code is
excluded.

I needed to fix up the .clang-format file so that all the header
includes are ordered properly. I could have sworn that it used to work
without the extra modification, but I guess not.

Signed-off-by: Philipp Schrader <philipp.schrader@gmail.com>
Change-Id: I64bb9f2c795401393f9dfe2fefc4f04cb36b52f6
diff --git a/y2019/vision/image_writer.h b/y2019/vision/image_writer.h
index f33cca7..1192368 100644
--- a/y2019/vision/image_writer.h
+++ b/y2019/vision/image_writer.h
@@ -24,6 +24,6 @@
 };
 
 }  // namespace vision
-}  // namespace y2017
+}  // namespace y2019
 
 #endif  // Y2019_VISION_IMAGE_WRITER_H_