This function is used to display a bmp file on the LCD screen.
The bmp file should be stored on SD Card.
BMP format should be 24-bit color, and no bigger than 128*160.
Bigger images will be cropped.
To use this method, you must initialize the SD card by calling Robot.beginSD() in setup().
Robot.drawBMP(filename, x, y)
filename: name of the bmp file to be displayed.
*x: x-axis of starting position on the screen.
*y: y-axis of starting position on the screen.
// Draws an image named "intro.bmp" from the SD card
//The image is pulled from sd card
// nothing happening here