Layouting should have default spacing
|Reported by:||axeld||Owned by:||yourpalal|
When using layouts like BGroupLayout their default item spacing is 0 pixels.
While it certainly makes sense to be able to set such a spacing for specific use cases, the typical way one would use a layout is to have a certain spacing that you currently have to set manually everytime (via BControlLook::DefaultItemSpacing()).
This spacing should be the default instead.