make edit area fit on screen+solution

Whenever you enter edit mode, any Basic card being edited (on its own or in a multi-edit context) will fit in one screen vertically, with enough space at the top and bottom for the card interface - i.e., including the wysiwig editing bar and Save/Cancel/Delete buttons.

For simple edit, scroll so that is what is on-screen. For multi-edit, scroll so that the top of the card is at the top of the screen.