Flatten providers package

The package hierarchy of the providers, providers/azure, providers/aws, etc has lead to the issue of code duplication that occurs due to the various providers being split into separate packages, and has led to the clusterinfo package being a dumping ground for various constants.

Moving all the structs that implement the CloudProvider interface into the top level providers package and removing the sub-packages would alleviate these issues.

Acceptance Criteria:

• All of the provider packages are moved into a singular package
• Code duplication across the providers implementations of the CloudProvider interface is reduced as much as possible.
• Constants present in the clusterinfo package that are more fit for the providers package are moved.