Multi size

[sshipman]

Added support for other text sizes, and re-organized the code for platformio src and lib conventions, which also makes Arduino compatibility simpler.

[sshipman]

Apologies for combining the changes with the re-org, I see it makes reviewing more difficult. In tb_display.cpp, please look at the new drawChar function which uses the M5.Lcd.drawChar(int32_t x, int32_t y, uint16_t c, uint32_t color, uint32_t bg, uint8_t size) rather than M5.Lcd.drawChar(int16_t uniCode, int32_t x, uint16_t y, uint8_t font); Use of the font version was the main thing keeping other text sizes from working.
Obviously, all the TEXT_HEIGHT stuff had to be moved to use something derived form text_size.
Miscellaneous changes include back-calculating the y coord of the first line which may now draw a partial line, and cleaning up init, which didn't need to switch-case. The use of the other drawchar made foreground and background colors explicit, so those are included as well. I'd have liked to be able to get them from M5.Lcd, but that doesn't seem to be available.