add optional K-factor to Dynamic

[DaveSkender]

Description

Add optional kFactor parameter to McGinley Dynamic; resolve #897

Checklist

• My code follows the existing style, code structure, and naming taxonomy
• I have put comments in my code, particularly for hard-to-understand areas
• I have performed a self-review of my code and included any verifying manual calculations
• I have added or updated unit tests that prove my fix is effective or that my feature works and achieves sufficient code coverage. New and existing unit tests pass locally and in the build (below) with my changes
• My changes generate no new warnings or other code analysis issues
• I have added or run the performance tests that depict optimal execution times
• I have made corresponding changes to the documentation