MiniSpartan6:
added ftdi chip config to switch between UART and Async FIFO.
added few WIP designs with either spwlight core, FIFO_deom IP...
Libs:
added SpaceWire Light IP (Works really well!)
started design of ahb_ftdi_fifo -> same protocol than AHBUART but over
FTDI's Async FIFO interface. This might lead to much faster
transfers UP to 12MB/s.
