stm3240g-eval: Add a configuration for testing the FB character driver at drivers/video/fb.c using the LCD frame driver front end at drivers/lcd/lcd_framebuffer.c. Appears to be fully functional.
stm3240g-eval: Replace the old-style stm32_appinit.c with tne new one from the STM32F4-Discovery
stm3240g-eval: Rename stm32_appinit.c to stm32_bringup.c to better match other architectures
