Lua: Replace uses of deprecated (moved) GUI2 functions

data/lua/wml-tags.lua

@@ -795,7 +795,7 @@ function wml_actions.remove_event(cfg)
 end
 
 function wml_actions.inspect(cfg)
-	wesnoth.gamestate_inspector(cfg)
+	gui.show_inspector(cfg)
 end
 
 function wml_actions.label( cfg )
@@ -958,7 +958,7 @@ end
 
 function wesnoth.wml_actions.story(cfg)
 	local title = cfg.title or helper.wml_error "Missing title key in [story] ActionWML"
-	wesnoth.show_story(cfg, title)
+	gui.show_story(cfg, title)
 end
 
 function wesnoth.wml_actions.cancel_action(cfg)

data/lua/wml/message.lua

@@ -295,7 +295,7 @@ local function message_user_choice(cfg, speaker, options, text_input, sound)
 			wesnoth.add_sound_source(speech)
 		end
 
-		local option_chosen, ti_content = wesnoth.show_message_dialog(msg_cfg, options, text_input)
+		local option_chosen, ti_content = gui.show_narration(msg_cfg, options, text_input)
 
 		if voice then
 			wesnoth.remove_sound_source("wml_message_speaker")

data/lua/wml/object.lua

@@ -62,7 +62,7 @@ function wml_actions.object(cfg)
 	if not silent then
 		wml_actions.redraw{}
 		local name = tostring(cfg.name or "")
-		wesnoth.show_popup_dialog(name, text, cfg.image)
+		gui.show_popup(name, text, cfg.image)
 	end
 
 	for cmd in wml.child_range(cfg, command_type) do