Add a param to pass a custom rule file path to the STIG constructor

There seems to be no way to pass a custom rule file path to the STIG constructor, as the data path is hardcoded:

static $DataPath = (Resolve-Path -Path "$($script:PSScriptRoot)\..\..\StigData\Processed").Path

It would be more convenient from debugging/testing perspective to add a RuleFile param to the STIG constructor.