Add a Credits menu. Fixes #2864.

mods/d2k/chrome/mainmenu.yaml

@@ -2,7 +2,7 @@ Background@MAINMENU:
 	X:(WINDOW_RIGHT - WIDTH)/2
 	Y:(WINDOW_BOTTOM - HEIGHT)/2
 	Width:250
-	Height:460
+	Height:500
 	Visible:true
 	Logic:MainMenuButtonsLogic
 	Children:
@@ -63,16 +63,23 @@ Background@MAINMENU:
 			Height:25
 			Text:Replay Viewer
 			Font:Bold
-		Button@MAINMENU_BUTTON_ASSET_BROWSER:
+		Button@MAINMENU_BUTTON_CREDITS:
 			X:45
 			Y:350
 			Width:160
 			Height:25
+			Text:Credits
+			Font:Bold
+		Button@MAINMENU_BUTTON_ASSET_BROWSER:
+			X:45
+			Y:390
+			Width:160
+			Height:25
 			Text:Asset Browser
 			Font:Bold
 		Button@MAINMENU_BUTTON_QUIT:
 			X:45
-			Y:390
+			Y:430
 			Width:160
 			Height:25
 			Text:Quit

mods/d2k/mod.yaml

@@ -56,6 +56,7 @@ ChromeLayout:
 	mods/ra/chrome/ingame-observerstats.yaml
 	mods/d2k/chrome/mainmenu.yaml
 	mods/ra/chrome/settings.yaml
+	mods/ra/chrome/credits.yaml
 	mods/d2k/chrome/lobby.yaml
 	mods/d2k/chrome/color-picker.yaml
 	mods/ra/chrome/map-chooser.yaml