Merge pull request #1853 from facebook/ahmed_file

.../experimental_dict_builders/benchmarkDictBuilder/Makefile

...experimental_dict_builders/benchmarkDictBuilder/README.md

...perimental_dict_builders/benchmarkDictBuilder/benchmark.c

...rimental_dict_builders/benchmarkDictBuilder/dictBuilder.h

...b/experimental_dict_builders/benchmarkDictBuilder/test.sh

contrib/experimental_dict_builders/fastCover/Makefile

contrib/experimental_dict_builders/fastCover/README.md

contrib/experimental_dict_builders/fastCover/fastCover.c

contrib/experimental_dict_builders/fastCover/fastCover.h

contrib/experimental_dict_builders/fastCover/main.c

contrib/experimental_dict_builders/fastCover/test.sh

...rib/experimental_dict_builders/randomDictBuilder/Makefile

...ib/experimental_dict_builders/randomDictBuilder/README.md

contrib/experimental_dict_builders/randomDictBuilder/io.c

contrib/experimental_dict_builders/randomDictBuilder/io.h

contrib/experimental_dict_builders/randomDictBuilder/main.c

...rib/experimental_dict_builders/randomDictBuilder/random.c

...rib/experimental_dict_builders/randomDictBuilder/random.h

contrib/experimental_dict_builders/randomDictBuilder/test.sh

contrib/largeNbDicts/largeNbDicts.c