allows teletext mode to work again
resolves issues with cursor movement and scrolling when certain combinations of cursor behaviour direction bits are set cursor behaviour better copes with odd font sizes
changes cursor drawing to make it more likely for the cursor block to be drawn in current text foreground colour
NB teletext mode will currently not work when x/y are swapped, or vertical is inverted - all scrolling inside the teletext mode support code is currently interpreted as a scroll upwards
allows teletext mode to work again resolves issues with cursor movement and scrolling when certain combinations of cursor behaviour direction bits are set cursor behaviour better copes with odd font sizes changes cursor drawing to make it more likely for the cursor block to be drawn in current text foreground colour
NB teletext mode will currently not work when x/y are swapped, or vertical is inverted - all scrolling inside the teletext mode support code is currently interpreted as a scroll upwards