Displays the current keyboard layout below the unlock indicator if more
than one xkb layout is configured or the show-keyboard-layout option is
given. The text is displayed with a background box.
Adds commandline options for text color, background color and border
color of the box as well.
Keeps track of unsuccessful authentication attempts via an int counter
in the state struct. Displays on the unlock indicator, but will be
replaced by the Caps Lock text if enabled.
This implements customization for the indicator as proposed in sway#2788 with comments from sway#3367 in mind.
The default behaviour does not change exept for the caps lock text color.
Since these changes seem to be lost in the split I've remade them.
