reorganise tree, forward_tree, base_tree includes

alib2std/src/forward_tree

+#ifndef __TREE_HEADER_WRAPPER_
+#define __TREE_HEADER_WRAPPER_
+
+#include <memory>
+#include <vector>
+#include <deque>
+#include <tuple>
+#include "iterator"
+#include "extensions/tree_base.hpp"
+#include "extensions/forward_tree.hpp"
+
+#endif /* __TREE_HEADER_WRAPPER */
+

alib2std/src/tree

@@ -8,7 +8,6 @@
 #include "iterator"
 #include "extensions/tree_base.hpp"
 #include "extensions/tree.hpp"
-#include "extensions/forward_tree.hpp"
 #endif /* __TREE_HEADER_WRAPPER */

alib2std/test-src/extensions/ForwardTreeTest.h

@@ -3,7 +3,7 @@
 #include <cppunit/extensions/HelperMacros.h>
 #include <compare>
-#include <tree>
+#include <forward_tree>
 class ForwardTreeTest : public CppUnit::TestFixture {
 	CPPUNIT_TEST_SUITE ( ForwardTreeTest );