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

main.lua

@@ -49,7 +49,7 @@ SCR.setSize(1280,720) -- Initialize Screen size
 BGM.setMaxSources(5)
 VOC.setDiversion(.62)
 
-WIDGET.setOnChange(function()
+ChangeButtonColorIfThemeUsed=function()
     if SCN.cur~='net_game' and SCN.cur~='custom_field' then
         local colorList=THEME.getThemeColor()
         if colorList then
@@ -60,7 +60,8 @@ WIDGET.setOnChange(function()
             end
         end
     end
-end)
+end
+WIDGET.setOnChange(ChangeButtonColorIfThemeUsed)
 
 -- Create shortcuts
 setFont=FONT.set
@@ -191,7 +192,7 @@ Z.setOnFnKeys({
 Z.setOnGlobalKey('f11',function()
     if not MOBILE then
         SETTING.fullscreen=not SETTING.fullscreen
-        applySettings()
+        applySettings('fullscreen')
         saveSettings()
     end
 end)