Slideshow of BMP images from microSD card.

This example uses the FatFS library for accssing a filesystem on a
microSD card. It will loop through the files present on the card. 
BMP files with a resolution less than the resolution of the screen
(320x240) will be displayed on the TFT. 

The demo has two modes of operation. If a file called "files.txt" is 
present on the root of the microSD card, this file will be read. The
BMP files will then be displayed in the order they are listed in the 
file.

If this file is not present, all files on the root of tile SD card is
looped through and displayed. If the BMP decoder cannot display a 
certain file, an error message is displayed.

WARNING:

SD2119 driver and GLIB graphics library are not intended for production
purposes, and are included here to illustrate TFT display driving only.
These components are subject to changes in API/usage and there will be 
no effort to keep compatibility, or to support this software in any way.

Board:  Silicon Labs EFM32-G2xx-DK Development Kit
Device: EFM32G290F128
Board:  Silicon Labs EFM32-G8xx-DK Development Kit
Device: EFM32G890F128
