New cpp folder structure

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

libs/kml/serdes_common.hpp

@@ -0,0 +1,38 @@
+#pragma once
+
+#include "coding/string_utf8_multilang.hpp"
+
+#include "geometry/point2d.hpp"
+#include "geometry/point_with_altitude.hpp"
+
+#include "type_utils.hpp"
+
+namespace kml
+{
+auto constexpr kDefaultLang = StringUtf8Multilang::kDefaultCode;
+auto constexpr kDefaultTrackWidth = 5.0;
+auto constexpr kDefaultTrackColor = 0x006ec7ff;
+
+template <typename Channel>
+uint32_t ToRGBA(Channel red, Channel green, Channel blue, Channel alpha)
+{
+  return static_cast<uint8_t>(red) << 24 | static_cast<uint8_t>(green) << 16 |
+         static_cast<uint8_t>(blue) << 8 | static_cast<uint8_t>(alpha);
+}
+
+std::string PointToString(m2::PointD const & org, char const separator);
+
+std::string PointToLineString(geometry::PointWithAltitude const & pt);
+std::string PointToGxString(geometry::PointWithAltitude const & pt);
+
+void SaveStringWithCDATA(Writer & writer, std::string s);
+std::string const * GetDefaultLanguage(LocalizableString const & lstr);
+
+std::string_view constexpr kIndent0 {};
+std::string_view constexpr kIndent2 {"  "};
+std::string_view constexpr kIndent4 {"    "};
+std::string_view constexpr kIndent6 {"      "};
+std::string_view constexpr kIndent8 {"        "};
+std::string_view constexpr kIndent10 {"          "};
+
+}  // namespace kml