Start to build specific Forez tour

lib/models/config.dart

@@ -1,5 +1,6 @@
 import 'dart:ui';
 
+import 'package:comunic/ui/routes/tour_route.dart';
 import 'package:meta/meta.dart';
 
 /// Application configuration model
@@ -18,6 +19,9 @@ class Config {
   final String appName;
   final String appQuickDescription;
 
+  // Entries for the welcome tour
+  final TourEntriesBuilder toursEntriesBuilder;
+
   const Config({
     @required this.apiServerName,
     @required this.apiServerUri,
@@ -26,6 +30,7 @@ class Config {
     this.splashBackgroundColor = defaultColor,
     this.appName = "Comunic",
     this.appQuickDescription,
+    this.toursEntriesBuilder,
   })  : assert(apiServerName != null),
         assert(apiServerUri != null),
         assert(apiServerSecure != null),