Switched to gcc 4.8.1 (fixes #35).

Additionally, the warnings produced by it have been fixed.
Upgraded to binutils 2.23.2.
Added a command in b to list all constructor calls.
Moved SConscript in libseoul to subdir nre.
Don't use the gcc-provided stuff, but our own (fixes #24).

That is, we have our own linker-scripts now, use -nostartfiles
and provide them ourself including calling __register_frame and
the global constructors.
This prevents that we need to write to the cross-compiler-folder,
avoids the eh_frame-problem in crtend.o of gcc we had previously.
Using our own linker-scripts gives us more control and removes
stuff we didn't need anyway.
Added an nm-command to b.
Adjusted cross-compiler scripts.
Merge branch 'gcc-4.8.1'

Conflicts:
	nre/b