feat(filter): YARA filter function

[rabbitstack]

YARA function enables the consolidation of signature and behavior-based detections by providing the ability to run YARA rules in Fibratus filters and rules. The yara function exposes the following arguments:

• pid|file|bytes, either the pid, filename or the byte chunk to be scanned by the YARA engine
• rules YARA rules that are executed on one of the above targets
• vars map of variable definitions to be replaced in YARA rules