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/StructInNestedNS.php

@@ -0,0 +1,52 @@
+<?php
+// automatically generated by the FlatBuffers compiler, do not modify
+
+namespace NamespaceA\NamespaceB;
+
+use \Google\FlatBuffers\Struct;
+use \Google\FlatBuffers\Table;
+use \Google\FlatBuffers\ByteBuffer;
+use \Google\FlatBuffers\FlatBufferBuilder;
+
+class StructInNestedNS extends Struct
+{
+    /**
+     * @param int $_i offset
+     * @param ByteBuffer $_bb
+     * @return StructInNestedNS
+     **/
+    public function init($_i, ByteBuffer $_bb)
+    {
+        $this->bb_pos = $_i;
+        $this->bb = $_bb;
+        return $this;
+    }
+
+    /**
+     * @return int
+     */
+    public function GetA()
+    {
+        return $this->bb->getInt($this->bb_pos + 0);
+    }
+
+    /**
+     * @return int
+     */
+    public function GetB()
+    {
+        return $this->bb->getInt($this->bb_pos + 4);
+    }
+
+
+    /**
+     * @return int offset
+     */
+    public static function createStructInNestedNS(FlatBufferBuilder $builder, $a, $b)
+    {
+        $builder->prep(4, 8);
+        $builder->putInt($b);
+        $builder->putInt($a);
+        return $builder->offset();
+    }
+}