Add basic python rule for flatbuffers

Not 100% sure I'm actually going to *use* this now that I've looked at
things more carefully, but it may be helpful for doing some data
analysis stuff.

Change-Id: I695cfe019639617da5baec4d45f5de71ad79b223
diff --git a/build_tests/test.fbs b/build_tests/test.fbs
new file mode 100644
index 0000000..71db3e7
--- /dev/null
+++ b/build_tests/test.fbs
@@ -0,0 +1,12 @@
+namespace aos.examples;
+
+table Foo {
+  value:int;
+}
+
+table Bar {
+  value:int;
+}
+
+root_type Foo;
+root_type Bar;