Entropy Apple: change time function called

[SparkiDev]

Description

Use clock_gettime_nsec_np and get the raw monotonic counter.

Testing

gather and analyse on ARM Mac

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[kaleb-himes]

Yields slightly higher entropy than previous use of mach_absolute_time! (0.9 bit / 8 bits generated previously ---> 1.2406 bits / 8 bits generated with this change.) Thank you @SparkiDev!

Full Report:

./analyse entropy-data-8bits-raw.dat 
Reading...
Processing Input...
Simple Analysis...
  Bit Stream Shannon Entropy              : 0.981703 7.853621
  8-bit Stream Shannon Entropy            :          2.959458

Analysing...
  Bit Stream Most Common Value Entropy    : 0.786090
  8-bit Stream Most Common Value Entropy  :          1.246894
Could not find p!!!
  Bit Stream Collision Entropy            : 1.000000
  Bit Stream Markov Entropy               : 0.845944
  Bit Stream Compression Entropy          : 0.257405
  Bit Stream t-Tuple Entropy              : 0.155079
  8-bit Stream t-Tuple Entropy            :          1.032288
  Bit Stream LRS Entropy                  : 0.211366
  8-bit Stream LRS Entropy                :          1.530848
  Bit Stream Multi MCW Entropy            : 0.786253
  8-bit Stream Multi MCW Entropy          :          1.248599
  Bit Stream Lag Prediction Entropy       : 0.231140
  8-bit Stream Lag Prediction Entropy     :          1.736904
  Bit Stream Multi MMC Entropy            : 0.168477
  8-bit Stream Multi MMC Entropy          :          1.246579
  Bit Stream LZ78Y Entropy                : 0.786100
  8-bit Stream LZ78Y Entropy              :          1.253661
                                            -----------------
              Minimum 8-bit Stream Entropy:          1.032288
                Minimum Bit Stream Entropy: 0.155079 1.240631
                  Assessed Minimum Entropy:          1.032288
                                            -----------------