No theme and default BG and patch BG bug when hitting F11 (#1070)

* Add setting slot for no theme & default BG

* Whitelist 4 seasons theme + blocking console's theme command if theme disabled

* Small update theme.lua

* Expose the WIDGET.setOnChange() to use in setting_video.lua

* Shorten "Use custom B.G." to "Custom B.G."

* Shorten theme code, and edit the UI

* Add lock BG

* Add VI translation

* Fullscreen patch

* Modify UI

* Small change

* Undo a mistake

parts/language/lang_en.lua

@@ -587,7 +587,11 @@ C. Gamepad
 
             bg_on="Normal B.G.",
             bg_off="No B.G.",
-            bg_custom="Use Custom B.G.",
+            bg_custom="Custom B.G.",
+            defaultBG="Default B.G.",
+            resetDbg="Reset default B.G.",
+            lockBG="Lock B.G.",
+            noTheme="Disable theme",
 
             blockSatur="Block Saturation",
             fieldSatur="Field Saturation",