Merge pull request #4274 from OlegHahm/ccnl_reimport

doc/doxygen/riot.doxyfile

examples/ccn-lite-relay/Makefile

examples/ccn-lite-relay/README.md

examples/ccn-lite-relay/main.c

pkg/ccn-lite/Makefile

pkg/ccn-lite/Makefile.include

pkg/ccn-lite/ccn-lite-riot.h

pkg/doc.txt

sys/include/net/af.h

sys/include/net/ethernet/hdr.h

sys/include/net/ethertype.h

sys/include/net/gnrc/nettype.h

sys/include/net/packet.h

sys/shell/commands/Makefile

sys/shell/commands/sc_ccnl.c

sys/shell/commands/shell_commands.c