- screen down and up TBD
- word movement (who does that) is TBD
- mouse to change windows (only works with one-window)
- the CollapseGap idea needs to be optimized, too sloppy right now
- make editing larger files faster by optimizing the Buffer stuff
- the error(s) from RuneAt which are currently panic-ing on check, should be handled differently
- and what's with func window2Buffer(w *Window) (window.go); needs the multiwindow update unfangled.
- implement the buffer as a piece-table, piece-chain?