ENH: Make the computeScreenMatrix() method from ScreenManager public and const.
ENH: Add a new method to ViewersLayout that maximizes or demaximizes a given viewer. A maximized viewer fills the entire window or the part of the window in a screen if the window is maximized to mulitple screens.
ENH: Viewers can be maximized or demaximized with double click, except when an incompatible tool is active.