Custom font set function (#2261)

* custom font set function
* update API symbols
* add example of custom font usage
* delete u8g2 dependency in example custom font
* rename to canvas_set_custom_u8g2_font
* now change the name in ALL places

Co-authored-by: あく <alleteam@gmail.com>
Co-authored-by: hedger <hedger@users.noreply.github.com>

applications/services/gui/canvas.h

@@ -146,6 +146,13 @@ void canvas_invert_color(Canvas* canvas);
  */
 void canvas_set_font(Canvas* canvas, Font font);
 
+/** Set custom drawing font
+ *
+ * @param      canvas  Canvas instance
+ * @param      font    Pointer to u8g2 const uint8_t* font array
+ */
+void canvas_set_custom_u8g2_font(Canvas* canvas, const uint8_t* font);
+
 /** Draw string at position of baseline defined by x, y.
  *
  * @param      canvas  Canvas instance