added spark core board

- [x] based on https://github.com/RIOT-OS/RIOT/pull/1752 <- wait for its merge first!

TODO:
- [x] test
- [x] restore examples/hello-world
- [ ] extend blacklists
- [x] add flash/debug scripts and make targets
- [x] update wiki
- [x] fix doxygen/authorship
what is this about? If the flasher needs a binary output, I would to change line 32 to:
`export OFLAGS = -O binary` and append
`export HEXFILE = $(ELFFILE:.elf=.bin)`