Touch and display driver subsystems reworked (and more) (#302)

- Refactored `TouchDevice`: it can now start/stop LVGL separately, and it has an optional `TouchDriver` interface
- Refactored `DisplayDevice`: it can now start/stop LVGL separately, and it has an optional `DisplayDriver` interface
- Updated all boards and drivers for above changes
- LVGL can now be stopped and (re)started on the fly
- Fixed issues with restarting Gui and Statusbar services
- Refactored `Gui` service to be class and renamed `Gui` to `GuiService`
- Fixed `Statusbar` service: forgot to deregister one of the icons
- Updated `esp_lcd_st7701` to v1.1.3
- `lv_textarea_create()` now automatically registers the hardware keyboard hooks (by wrapping the function)
- Fixed and updated `tactility.py`
- Cleanup of a lot of code
- `BootInitLvglBegin` and `BootInitLvglEnd` are replaced by `LvglStarted` and `LvglStopped`.
- Introduced `tt::service::State` which is accessible via `tt::service::getState()` (and internally via `ServiceInstance`)
- Started replacing `#define TAG` with `constexpr auto TAG = "..";`

TactilityC/Include/tt_lvgl_keyboard.h

@@ -50,14 +50,6 @@ bool tt_lvgl_hardware_keyboard_is_available();
  */
 void tt_lvgl_hardware_keyboard_set_indev(lv_indev_t* device);
 
-/**
- * Glue code for the on-screen keyboard and the hardware keyboard:
- *  - Attach automatic hide/show parameters for the on-screen keyboard.
- *  - Registers the textarea to the default lv_group_t for hardware keyboards.
- * @param[in] textarea
- */
-void tt_lvgl_keyboard_add_textarea(lv_obj_t* textarea);
-
 #ifdef __cplusplus
 }
 #endif