rpg_walk: save, main menu, load; action card texts are translated

Covers the empty dialog box after loading a save and the untranslated
action cards in battle. Docs: the world is built from engine mods, not a
novel engine.

src/Data/RpgMap.cs

@@ -9,7 +9,7 @@ namespace Cthangover.Mods.Rpg
     /// scene that shows it: entering scene <c>X</c> (any <c>switch_scene X</c>, a
     /// teleport, the return from a battle, loading a save) mounts map <c>X</c>
     /// over the shell. Because the scene stays an ordinary scene, everything the
-    /// novel engine attaches to scenes works on a map unchanged — entry
+    /// engine attaches to scenes works on a map unchanged — entry
     /// scenarios, ambience and music from <c>scenes/X.json</c>, the default
     /// background (which also becomes the backdrop of battles started here),
     /// saving rules.

src/World/RpgWorldHost.cs

@@ -14,7 +14,7 @@ namespace Cthangover.Mods.Rpg
     /// It follows the scene lifecycle: entering a scene whose name is a map id
     /// mounts that map (<see cref="RpgWorldView"/>) and shows the dark backdrop;
     /// any other scene leaves the host empty and invisible, so a game can mix
-    /// novel scenes and map scenes freely. The shell is rebuilt after battles,
+    /// picture-and-dialogue scenes and map scenes freely. The shell is rebuilt after battles,
     /// so the host is too; the position survives in <see cref="RpgState"/>.
     /// <para/>
     /// <see cref="Current"/> is the host of the live shell, used by teleports