exchanged BOARD_BLACKLIST with FEATURES_REQUIRED in the example Makefile
added cpp as feature for board native
Merge pull request #1988 from BytesGalore/riot_and_cpp_blacklist_to_required_feature

examples/riot_and_cpp: exchanged BOARD_BLACKLIST with FEATURES_REQUIRED
added empty _kill() stub
removed _kill_r() function already implemented in newlib
added missing CXX exports
[SQUASH ME] added cpp feature to msba2 board