Add option to all widgets to autohide

[jfgilliam]

Have all widgets that only work when you're in the car to hide themselves when you are not in the car. Also, if the widget only works when you're not in the car to hide when you are in the car. There are also widgets that only work in a replay and some that do not work in a replay. Have them auto hide as appropriate.

Use the AUTOHIDE option on the menu. Do not make it default. Only works if you make the widget transparent.

[jfgilliam]

Also add API to hide and unhide all. Then add those to VA.