Add script to export JSON for ATT&CK Navigator

The source of `CompareSysmonTo-MITRE_ATTCK.ps1` script is
from olafhartong#80

This script is useful and cool!
Thanks to nicpenning for his contribution

Finally, modify some code in the script according to my needs, such
as loading MITRE ATT&CK v11.0

Author: stavhaygn