Introduce the new class NameMapper.

This class is used to map an id (uuid) to a name (potentially human
readable).

This will be use by the server to or renderer to use a different "name"
than the id.

The default NameMapper provided use the id as a name.

include/name_mapper.h

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2019 Matthieu Gautier <mgautier@kymeria.fr>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU  General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#ifndef KIWIX_NAMEMAPPER_H
+#define KIWIX_NAMEMAPPER_H
+
+#include <string>
+
+namespace kiwix
+{
+
+class NameMapper {
+  public:
+    virtual ~NameMapper() = default;
+    virtual std::string getNameForId(const std::string& id) = 0;
+    virtual std::string getIdForName(const std::string& name) = 0;
+};
+
+
+class IdNameMapper : public NameMapper {
+  public:
+    virtual std::string getNameForId(const std::string& id) { return id; };
+    virtual std::string getIdForName(const std::string& name) { return name; };
+};
+
+}
+
+#endif