Try compiling the tool chain for leon3
Merge branch 'leon3' of login1.ida.ing.tu-bs.de:/projects/ccc/repositories/gitroot/genode into leon3
Leon3: backport leon3 support from gcc 4.9.1 and binutils 2.24
Leon3: work around shared libgcc issue
Leon3: add missing HAVE_AS_LEON patch
Leon3: fix L4 cpu config
Leon3: use standard tool chain path
Leon3: add script that builds a patched qemu binary for the LEON3
Leon3: incremental progress

- update foc repo
- add build_boot_image proc
- add missing core files
- adapt spawn_qemu