Corrected issue 70, 'pack' instruction on IBM AIX

Added : fullbench : can select compression tests or decompression tests
Removed extern inline, for compatibility with GNU89, as reported by Maciej Adamczyk
lz4.c : made forceinline more explicit
Decompression : corrected corner case behaviors (inputSize == 0 and outputSize == 0), thanks Adrien for detailed suggestions
Makefile : Removed -march=native parameter, due to incompatibility with some GCC versions