Feature: Support multiple parameters per Rule

[jpower432]

Feature objectives

Trestle supports multiple parameters per rule. To fully support documents created through trestle, multi-parameter rules should be supported.

Caveats / Assumptions

• Parsing multiple parameters within a RuleSet through OSCAL properties as complexity to the parsing logic under the rules package

Completion Criteria

• Rule type in extensions is updated to add an optional slice of parameters
• References to Rule.Parameter are updated to process the new type