Commit Briefs
simplify minibuffer/echoarea redraw
split the logic into two functions: one to render the echoarea and one to rendere the minibuffer (when it's active).
move minibuffer-related fns to their own file
and a bit of foreshadowing... :)
rename minibuf to echoarea
there's a close relationship between the echoarea and the minibuffer, but let's call it echoarea for now.
bugfix: print the trailing face until the right column
This would leave the last column white if !olivetti-mode and a background color for some body lines