Merge pull request #4217 from haukepetersen/opt_tests_makefiles

boards/fox/include/at86rf2xx_params.h

boards/fox/include/board.h

tests/driver_adt7310/Makefile

tests/driver_at86rf2xx/Makefile

tests/driver_dht/Makefile

tests/driver_hdc1000/Makefile

tests/driver_hih6130/Makefile

tests/driver_ina220/Makefile

tests/driver_isl29020/Makefile

tests/driver_isl29125/Makefile

tests/driver_kw2xrf/Makefile

tests/driver_l3g4200d/Makefile

tests/driver_lis3dh/Makefile

tests/driver_lps331ap/Makefile

tests/driver_lsm303dlhc/Makefile

tests/driver_mag3110/Makefile

tests/driver_mma8652/Makefile

tests/driver_mpl3115a2/Makefile

tests/driver_mpu9150/Makefile

tests/driver_mq3/Makefile