Add data structure to allow identification of via-way turns during creation of edge-based-graph

initial version of handling via-way turn restrictions (this is dirty)

 - requires update of data structures
 - requires clean-up
 - requires optimisation

src/updater/updater.cpp

@@ -511,7 +511,7 @@ updateConditionalTurns(const UpdaterConfig &config,
 
         // only add restrictions to the lookups if the restriction is valid now
 
-        if (node_or_way.flags.is_only)
+        if (node_or_way.is_only)
         {
             is_only_lookup.lookup.push_back({std::make_tuple(c.from, c.via), c.to});
         }