FTXUI supported only the 16 colors palette.
This patch adds support for the 256 palette and the TrueColor(8×8×8)
mode.
This was made by kerdelos@ and fixes issue:
https://github.com/ArthurSonzogni/FTXUI/issues/45
Co-authored-by: Damien D <kerdelos@gmail.com>
Co-authored-by: Arthur Sonzogni <sonzogniarthur@gmail.com>
