As pointed out in the initial code review of #4351, some of the steps
from the standard EBS builder were (intetionally) omitted. It turns out
that these actually are useful, and the original rationale for the
omission was wrong. Consequently, this commit adds in the following
steps:
- `StepPrevalidate`
- `StepTagEBSVolumes`
- `StepDeregisterAMI`
- `StepCreateEncryptedAMICopy`
- `StepAMIRegionCopy`
- `StepModifyAMIAttribute`
- `StepCreateTags`
We also fix the interpolation filter and documentation to reflect these
additions, though the majority were already documented and just not
functional.