Convert aos over to flatbuffers

Everything builds, and all the tests pass.  I suspect that some entries
are missing from the config files, but those will be found pretty
quickly on startup.

There is no logging or live introspection of queue messages.

Change-Id: I496ee01ed68f202c7851bed7e8786cee30df29f5
diff --git a/aos/vision/image/BUILD b/aos/vision/image/BUILD
index 21dbbb8..9b6d30a 100644
--- a/aos/vision/image/BUILD
+++ b/aos/vision/image/BUILD
@@ -5,6 +5,9 @@
 cc_library(
     name = "image_types",
     hdrs = ["image_types.h"],
+    deps = [
+        "@com_google_absl//absl/strings",
+    ],
 )
 
 cc_proto_library(