* elements which possibly depended on this depend now on `visibility` of element added
* changed everywhere returns on addWidget
* checked layouts (vertical, horizontal, pagedbox, gridlayout)
* tryAddWidget was redundant to addWidget, with Rect fixes and log it's not needed
* With changes in BoundingBox simplified axis use in BoxLayout
* Add widget moves elements to it's place, resize is not thought through and for now is removed
* Improved bluetooth library interface write in one demand
* can start scan
* not used BT options hidden
* still some issues on flood - transaction style interface should be considered
