Made sure all namespace test files get generated.

Also included them in the C++ test.

Change-Id: Ib0c8470f0aacdf16616c27494abdda57a010195d
Tested: on Linux.

tests/namespace_test/NamespaceA/NamespaceB/TableInNestedNS.py

@@ -0,0 +1,23 @@
+# automatically generated, do not modify
+
+# namespace: NamespaceB
+
+import flatbuffers
+
+class TableInNestedNS(object):
+    __slots__ = ['_tab']
+
+    # TableInNestedNS
+    def Init(self, buf, pos):
+        self._tab = flatbuffers.table.Table(buf, pos)
+
+    # TableInNestedNS
+    def Foo(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            return self._tab.Get(flatbuffers.number_types.Int32Flags, o + self._tab.Pos)
+        return 0
+
+def TableInNestedNSStart(builder): builder.StartObject(1)
+def TableInNestedNSAddFoo(builder, foo): builder.PrependInt32Slot(0, foo, 0)
+def TableInNestedNSEnd(builder): return builder.EndObject()