Slovak UTF-8 translation

Add polish font for GLCD displays only.
HD44780 work properly without polish character.
Update language_pl.h.

The non utf8 version of turkish is a bit unhandy.

Delete `language_tr.h`
Rename `language_tr_utf.h` to `language_tr.h`
Provide a propper utf8-mapper for Turkish and use it.

Add check for Turkish Font before setting better font for graphic displays

Make MAPPER_NON the fall back mapper - if no other is defined.
One list less to maintain.

Following up on #3231

Keep "astyled" reformatting

Apply `ENABLED` / `DISABLED` macros to language-related files.

Automatic selection was to unflexible.

Updated documentation

Updated language files to new logic and documentation.

Updated bdf2u8g.exe

Top -> down
- Decide what output function is to use.
- Precautions. If non of the DISPLAY_CHARSET_HD44780's is selected fall back to Japanese.
- When we are not on the dogms setup a mapping table depending on display type and mapper.
- If we are on dogm we use ONE To ONE mapping - except kanji.
- select and define one of the mapping functions.