Do not consider EC2 instances in terminated state.

They aren't coming back :)
Handle exact tags.
Use IAM-provided credentials if indicated.
Add sane entry point for docs build.
Updated index.rst with --use-iam-profile stuff.

Regenerated the pertinent portion of README by:

cd docs
make zonify.txt
Explicitly sort output hashes.
Merge utility.
Merge pull request #2 from paxan/use-iam-profile

Use IAM-provided credentials if indicated.
Merge branch 'merge'