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/meson.build

@@ -10,7 +10,8 @@ headers = [
   'reader.h',
   'entry.h',
   'searcher.h',
-  'kiwixserve.h'
+  'kiwixserve.h',
+  'name_mapper.h'
 ]
 
 install_headers(headers, subdir:'kiwix')