Preliminary integration of the tile plugin

include/engine/api/tile_parameters.hpp

@@ -0,0 +1,28 @@
+#ifndef ENGINE_API_TILE_PARAMETERS_HPP
+#define ENGINE_API_TILE_PARAMETERS_HPP
+
+namespace osrm
+{
+namespace engine
+{
+namespace api
+{
+
+struct TileParameters final
+{
+    unsigned x;
+    unsigned y;
+    unsigned z;
+
+    // FIXME check if x and y work with z
+    bool IsValid()
+    {
+        return z < 20;
+    };
+};
+
+}
+}
+}
+
+#endif