Added the 3Com 3C503 Network card;

Several bug fixes;
Preliminar addition of the SDL 2 renderer (does not yet work correctly in full screen mode);
SCSI devices no longer have configurable LUN's (this matches the configurability of real SCSI devices);
SCSI LUN's are now handed by the device's handler;
Removed all unused strings;
Removed some unused code files;
Significantly rewrote the bus mouse emulation.

src/pit.c

@@ -2,6 +2,7 @@
   Write B0
   Write aa55
   Expects aa55 back*/
+#include <inttypes.h>
 #include <stdio.h>
 #include <stdint.h>
 #include <string.h>