cleanup of a few tested/resolved todos

src/epd2in9/mod.rs

@@ -221,8 +221,7 @@ where
 
         // clear the ram with the background color
         let color = self.background_color.get_byte_value();
-
-        //TODO: this is using a big buffer atm, is it better to just loop over sending a single byte?
+        
         self.interface.cmd(spi, Command::WRITE_RAM)?;
         self.interface.data_x_times(spi, color, WIDTH / 8 * HEIGHT)
     }