Support for STIG Questionnaires and .CKL Files

[ptcrash]

I have a need to track compliance with STIGs and SRGs with our products. Typically, compliance with a STIG can be tracked with a tool like STIG Viewer, which saves a checklist in a standard format as a .CKL file.

There are hundreds of STIGs and SRGs and their corresponding checklists can be viewed on this website but are typically triaged through a tool like OpenRMF or NUWCDIVNPT/stig-manager. But it would make a lot of sense to bring similar featuring into DefectDojo since handling questionnaires is already a feature in this tool and the other open-source tooling on the market don't add a significant amount of features outside of just managing a bunch of .CKLs.

This would likely be a big change for DefectDojo and might be a good candidate for v3. I'd be willing to help work on adding the feature but I'm not even sure where v3 even lives right now.