New cpp folder structure

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

libs/routing/transit_graph_loader.hpp

@@ -0,0 +1,25 @@
+#pragma once
+
+#include "routing/edge_estimator.hpp"
+#include "routing/index_graph.hpp"
+#include "routing/transit_graph.hpp"
+
+#include "routing_common/num_mwm_id.hpp"
+
+#include <memory>
+
+namespace routing
+{
+class MwmDataSource;
+
+class TransitGraphLoader
+{
+public:
+  virtual ~TransitGraphLoader() = default;
+
+  virtual TransitGraph & GetTransitGraph(NumMwmId mwmId, IndexGraph & indexGraph) = 0;
+  virtual void Clear() = 0;
+
+  static std::unique_ptr<TransitGraphLoader> Create(MwmDataSource & dataSource, std::shared_ptr<EdgeEstimator> estimator);
+};
+}  // namespace routing