Refactor configuring AWS account

[lander2k2]

Currently, the command tptctl config aws-account creates an AwsAccount object in threeport and configures a user's AWS account with IAM resources. This task includes the following: Add the command tptctl create aws-account to create the AwsAccount object in threeport with an optional flag --config-aws to perform the IAM resource creation in user's AWS account. Chang the tptctl config aws-account command to only perform the config step.

This allows creation of the threeport API object and AWS account config to be performed in a single or multiple steps depending on user preference.

Related to: https://app.asana.com/0/0/1205775473663704/f