Auto-add watches for .bss and .data segment data

[nirvdrum]

Other ASM debuggers I've used in the past will set up watches for values from the .bss and .data segments. I've found this to be handy, particularly when paired with their addresses. I think it'd be very nice if SASM could auto-add these values to the watches list. Since the declarations will indicate the type, that information could be integrated into the watch as well so there's no need to guess at them. Alternatively, it could be nice to have a dedicated view for values from these segments separate from the watches list.