See https://github.com/gdamore/tcell/pull/431

* Added tests for `LightRenderer`

* Added common SHIFT, ALT and ALT+SHIFT key sequences

* Added common CTRL key sequences

* Added common CTRL+ALT, CTRL+SHIFT, CTRL+ALT+SHIFT key sequences

* Added proper xterm META modifier handling

according to https://github.com/joejulian/xterm/blob/defc6dd5684a12dc8e56cb6973ef973e7a32caa3/input.c#L357-L375

* Fix `ctrl-backspace` and `ctrl-alt-backspace`

* Fix broken tcell tests on windows by swallowing Resize events

* Added tests for  FullscreenRenderer

* Removed own fork of tcell and updated tcell to 2.9.0

tcell 2.9.0 is needed for `Ctrl-Alt-*` and `Ctrl-Alt-Shift-*` shortcuts in Windows

* Replace conditional checks with switch statements to improve readability

* Replace long conditionals with constant slices to improve readability

* Bind `ctrl-bspace` (`ctrl-h`) to `backward-delete-char` by default

Since we now distinguish between Backspace and Ctrl-Backspace, Ctrl-Backspace should trigger the same action as Backspace by default. In that way nothing changes for the user but you can bind other actions to Ctrl-Backspace when desired.

Options:
  --footer=STR             String to print as footer
  --footer-border[=STYLE]  Draw border around the footer section
                           [rounded|sharp|bold|block|thinblock|double|horizontal|vertical|
                            top|bottom|left|right|line|none] (default: line)
  --footer-label=LABEL     Label to print on the footer border
  --footer-label-pos=COL   Position of the footer label
                           [POSITIVE_INTEGER: columns from left|
                            NEGATIVE_INTEGER: columns from right][:bottom]
                           (default: 0 or center)

The default border type for footer is 'line', which draws a single
separator between the footer and the list. It changes its position
depending on `--layout`, so you don't have to manually switch between
'top' and 'bottom'

The 'line' style is now supported by other border types as well.
`--list-border` is the only exception.

Close #4316

Close #4233