Add stdlib::get_from_bucket functionality and tests

[jeffmccune]

Test coverage for the following functions which are optionally included via feature flags.

• stdlib::init_gsutil_crcmod_el
• stdlib::get_from_bucket

Do not merge until

• [x] gsutil related integration tests have been added
• [x] #12 merged
• [x] #14 merged

[jeffmccune]

@adrienthebo This is ready for review. It's based off #14

[jeffmccune]

Next steps on this are to create a gsutil2 instance which is a copy of the current gsutil1 instance.

• gsutil2 will have storage.objects.get access for the positive test
• gsutil1 will retain the current behavior to include a negative test of retry behavior when access is denied.

[adrienthebo]

@jeffmccune we're getting CI failures, could you take a look? Also, it looks like we're getting some odd formatting in CI, you may want to disable color in the terraform verifier like what we're doing for the project factory .kitchen.yaml.

[jeffmccune]

Will do, let's leave this on hold until I clean up the failures.

[jeffmccune]

@adrienthebo I fixed up the tests. I've left the sequence of patches in their "fixup" commits to make review easier. I'd like to avoid adding much more code to this PR to prevent it from growing larger than it already is. Could you please review again, putting aside git hygiene. If approved, I'll rebase ahead of merge. What do you think?

Regarding my comment, "Next steps on this are to create a gsutil2 instance which is a copy of the current gsutil1 instance." I propose that be moved to a future, smaller, PR.

[jeffmccune]

If you could lead me along the path with a link to prior art, I'm happy to do it here as part of the rebase work that needs to be done. Otherwise it's probably best to do this in a separate PR as I'd be covering new (to me) ground moving the logic to the converge / create steps.

[morgante]

I vote in favor of merging now and adding the retry logic in a follow-on PR.