add flatbuffers

commit 6da1cf79d90eb242e7da5318241d42279a3df3ba
Author: Max Burke <max@urbanlogiq.com>
Date:   Sun Jan 19 14:47:28 2020 -0800

    [rust] Add use declarations to Rust-generated bindings for imported FB definitions (#5645)

    * Bugfix for Rust generation of union fields named with language keywords

flatbuffers/tests/namespace_test/NamespaceA/NamespaceB/EnumInNestedNS.py

@@ -0,0 +1,9 @@
+# automatically generated by the FlatBuffers compiler, do not modify
+
+# namespace: NamespaceB
+
+class EnumInNestedNS(object):
+    A = 0
+    B = 1
+    C = 2
+