Refactored RouteComparison.comparison_check function name and logic
Refactored RouteComparison.comparison_check function name and logic

- Changed RouteComparison.comparison_check to
  RouteComparison.difference_check_with_threshold for better abstraction

- Changed threshold calculation to trigger if calculation equals to or
  is greater than the threshold; added additional case when threshold is
  set to 0/0.0 to prevent the threshold from triggering when there are
  no differences between the two lists

- Explicitly return False at end of function

- Added ability to compare number values to an iterable

spgreen/psTrace