(cleanup): Move types to their own files

[cartermckinnon]

What type of PR is this? /kind cleanup

What this PR does / why we need it:

This begins some overdue refactoring of the AWS Cloud implementation. This PR has no code changes, it simply moves existing types (with their associated functions) to separate source files, in an attempt to whittle-down the ~4k line aws.go.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[k8s-ci-robot]

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[cartermckinnon]

@mmerkes tackling some cobwebs PTAL

[cartermckinnon]

Are there any actual changes to the lines, or is this a straight cut/paste?

Just cut/paste + license headers.

[mmerkes]

/lgtm /approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mmerkes

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