Added support for Auto Scaling Instances

[timkra]

I´ve added a function to get Instances that are running in Auto Scaling Groups. The groups can be filtered by a Tag. The Instances in the group must be InService.
The data returned is the same as from the EC2 Import.

[lippserd]

Hi @timkra,

Thanks for the PR!

Besides the InService filter, is there anything else that prevented you from using the EC2 instance import in combination with the Director functionality to restrict the import based on filters?

All the best,
Eric