Add Unicode support via UnifontEX

[stgiga]

I saw your project and it's a LOT like what I wanted to do, especially the e-mail and Winamp modes. I feel like Unicode usage would do it justice, and so my idea was to use my LCD library builds of UnifontEX for LVGL, U8G2, UCGLIB, and Adafruit_GFX (in practice, LVGL is your best bet unless you use an Arduino Portenta H7, which allows U8G2 or UCGLIB, of which the latter is just possible). UnifontEX is an extended GNU Unifont that merges Plane 0 and Plane 1 as best as possible, and you can for instance use a LOT of its symbols to represent an e-mail inbox status, media player status, and of course stuff that isn't the ASCII of the Hitachi controller. UnifontEX is 8x16+16x16, but it looks just like a character LCD. I'm even debating ordering a Noritake VFD with its TTF2PNG build (Public Domain in my jurisdiction) in it.

I may not have the funds to do the non-desktop version, but I feel like Unicode support would do you a world of good, if UnifontEX's sample text at https://stgiga.github.io/UnifontEX

And the Unicode support is Unicode 15.1 so it's definitely a good idea.