GitLab

* Create `NewAWSProvider` with `AWSConfig` struct

Rather than calling `NewAWSProvider` with a list of objects, you will
now call it using a new `AWSConfig` struct. This allows for clearer
declarations of variables which becomes even  more important as more
variables are added.

* Add `aws-max-change-count` flag

Adding a new `aws-max-change-count` flag to override the default max
change count on the aws provider.

Included updated tests with a new `defaultMaxChangeCount` constant and
tests for setting the value as a flag and as an environment variable.

* Update CHANGELOG.md

Updating CHANGELOG.md with 'Add aws max change count flag' PR.