dynamically generate key pairs instead of requiring one to be already setup

[rustyrazorblade]

This improvement will do the following:

1. Eliminate the need to explicitly create a key using the AWS control panel or the aws CLI tool
2. Ask for the AWS key and secret up front.
3. Move user profile information from a profile_name.yaml into a directory, `profile_name/settings.yaml"
4. Create a key in AWS and save the private key to the user profile. Use a randomly generated unique name, such as keyName: "tlp-cluster-368b8370-e148-4590-85b0-573ffaf1ca45" to avoid conflicts. Future work may add more identifiers.
5. Remove the question from the startup process asking for the key name & private key location
6. Update documentation accordingly.