window: change internal color representation
visualizer: stereo ellipse: make radius of each ring constant
window: add support for textual representation of background color
help: display available colors and numbers that identify them
doc: mention support of 256 colors and describe setting background color
visualizer: stereo ellipse: scale the samples to fill the whole screen
format: implement generic format parser and printer
wide string: a few adjustments
remove silly comment after namespaces
format: fix error reporting with wide strings
window: use simpler functions than wprintw if possible
window: remove debug print
format: support 256 colors and backgrounds in formats
doc: update description of formats
actions: toggle interface: unlock progressbar
window: fill background color on clearing to EOL
window: support 'previous' background value for better composability
settings: buffer: apply helper function
format: add flags to refine parsing and printing of the AST
settings: song_status_format: forbid alignment mark