pubsys: add AMI registration/copying

[tjkirch]

Description of changes:

commit fdffc56bb4a7eaae368d16b5ca974c65b0063dcc
Author: Zac Mrowicki <[email protected]>
Date:   Thu Jul 30 23:30:39 2020 +0000

    Add the "ami" subcommand to pubsys

    This lets you register an AMI from the latest build and copy it to a list of
    regions.

commit 659fe384c7f2990294080f712efbb28a4aaf2fcd
Author: Zac Mrowicki <[email protected]>
Date:   Tue Jul 28 23:25:43 2020 +0000

    Make all fields of Infra.toml optional

    Pubsys subcommands do not use the same parts of Infra.toml, so they have
    to be optional if we want to have a common config file.  The subcommands
    will confirm that the necessary fields are present.

Infra.toml.example was updated with the configuration needed for building AMIs; only a region list is necessary, and that can be overridden by specifying -e PUBLISH_REGIONS if desired. You can also override the AMI name and volume sizes, if desired.

Testing done:

Used cargo make ami to register single AMIs, register/copy AMIs in multiple regions, register with global and regional roles. A registered Bottlerocket aws-k8s-1.17 AMI ran/connected OK. Also reran cargo make repo to ensure existing functionality wasn't affected by config change.

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[tjkirch]

^ This push fixes the coldsnap dependency in Cargo.toml to actually use it from crates.io.

[zmrow]

🦓

[bcressey]

Also this is amazing, nice work!

[tjkirch]

I'm not able to push the change until @zmrow's back, but this addresses @bcressey's feedback above: https://gist.github.com/tjkirch/b0ac076be189af44551a20f5c5bed7c5 Still able to make AMIs OK.

[tjkirch]

^ This push addresses @bcressey's comments above, as in my gist above.

[tjkirch]

^ This push is just a rebase on develop to fix conflicts.

[zmrow]

^ This push is just a rebase on develop to fix CI.

[tjkirch]

^ This push moves PUBLISH_AMI_NAME to the [env.development] section of Makefile.toml, which is necessary so that when you change BUILDSYS_ARCH it can actually insert the arch into the AMI name. Unfortunately this means it can't be overridden, for the same reasons we have trouble with other layered variables in Makefile.toml; we should find a more comprehensive solution for that.

[webern]

Nice!