Floating windows #23
Description
A Floating window is an Component which can have an arbitrary position on the screen over any ordinary Component. This means that the boundary check should be relaxed for floating windows and they should be able to be added anywhere.
The caveat is that a floating window should not overlap with any other floating window.
Depends on #24 because it will introduce the Layerable stack
Related to #22 because Drag'n drop is the main use case for moving floating windows