New cpp folder structure

Signed-off-by: Alexander Borsuk <me@alex.bio>

libs/base/stl_iterator.hpp

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <boost/iterator/iterator_facade.hpp>
+
+namespace stl_iterator_detail
+{
+struct Dummy
+{
+  template <class T> Dummy & operator=(T const &) { return *this; }
+};
+}  // namespace stl_iterator_detail
+
+class CounterIterator :
+    public boost::iterator_facade<CounterIterator, stl_iterator_detail::Dummy, boost::forward_traversal_tag>
+{
+  size_t m_count;
+public:
+  CounterIterator() : m_count(0) {}
+  size_t GetCount() const { return m_count; }
+
+  stl_iterator_detail::Dummy & dereference() const
+  {
+    static stl_iterator_detail::Dummy dummy;
+    return dummy;
+  }
+  void increment() { ++m_count; }
+};