Provide "estimate" and "cost" of a cluster

/kind feature /area clusterawsadm /priority important-longterm /triage accepted

Describe the solution you'd like

As a user of CAPA i would like to:

• get an estimate of the cost for a cluster before i create it based on the generated manifests. This is termed an estimate as it won't take into account all the resources....just the big ticket items such as EC2 instances.
• get the cost of an already created cluster. As all the resources are created we can get a more accurate figure and this is deemed the cost of the cluster.

We need to implement this with the following in mind:

• We should be able to change/choose the way that prices for a particular resource type are retrieved. Initially, lets use the AWS Pricing API and Infracost. But in the future it could be a file on disk.
• We should design with integration in mind:
  • Integration of the CLI into a pipeline, with options on the output format of the price (i.e. text, table, yaml, json)
  • Integration as a package by being imported into another application

Anything else you would like to add: [Miscellaneous information that will assist in solving the issue.]

Environment:

• Cluster-api-provider-aws version:
• Kubernetes version: (use kubectl version):
• OS (e.g. from /etc/os-release):