Usability: Show AWS region where the key does not exist

[earthquakesan]

When creating new deployment, if the ssh key pair is not in the region, graviton will spit an error:

Creating the new deployment stardog-cloud
Failed: The AWS keyname stardog-ssh-key does not exist

For improving the readability, I suggest to modify the error output to:

Failed: The AWS keyname stardog-ssh-key does not exist in the region Frankfurt

[earthquakesan]

P.S. It took me couple of minutes to figure out that I have a keypair in the wrong region

[pdmars]

Thanks for the suggestion. More detailed output as to the exact reason and region would definitely be helpful.

[earthquakesan]

If retrieving region is not feasible, the next helpful thing would be to output all the key names to the user. They are retrieved anyway, that will be just a line of code.

i.e.
"Could not find key 'stardog-ssh-key' in the keys available on AWS. The available keys are: ['key-1', 'key-2', 'key-3'].