Update to gcc-4.8.0

Added libgcc patch for gcc-4.8.0 and updated the SAT script. 
Tested both on Windows 7 and Ubuntu 12.10 - builds were successfully finished for main features (binutils, gcc, newlib (and newlib-nano), gdb), the resulting toolchain was tested to build firmwares for stm32f407 and stm32f215 with previously compiled libopencm3.
However, I wasn't able to build libopencm3 using the toolchain due to the following error:
../../cm3/vector.c: In function 'reset_handler':
../../cm3/vector.c:70:1: internal compiler error: in advance_target_bb, at shed-rgn.c:3552
0x78eb92 advance_target_bb
I'll try to investigate that error later, but if someone has any information about it I'd be grateful to hear it.On the good side - I've noticed a significant footprint size reduction compared to 4.7.2 (but maybe it's just for my code).