[Request] Add scripts from attack-scripts repo

[jondricek]

Is your feature request related to a problem?

The only problem is that the functionality is split between two different repositories and ought to be condensed into a single one.

Describe the solution you'd like

Combine the scripts from https://github.com/mitre-attack/attack-scripts/ with this repository.

Describe alternatives you've considered

Keeping both repositories adds an extra burden of maintenance. It could be done, but I think it makes the most sense to not need to check both places all the time.

Additional context

None (at this time)