Improve missing credentials error & Setup Default AWS profile via CLI

[DavidWells]

TLDR: http://www.screencast.com/t/1UR8eOMoU (1min 30 sec)

Upgrading from 0.5 to 1.0 causes some weird issues, all relating to the ~/.aws credentials file containing old account information from v0.5 and expecting the [default] aws credentials (described here linking to the setup instructions )

This is something I think we could fix with a sls setup command in the CLI to clean up the ~/.aws credentials file and setup the [default] aws credentials if they don't exist yet via the command prompt.

Serverless Framework Version:

1.0

Operating System:

OSX

Suggested Behavior:

Actual Behavior:

This error is displayed with no supporting information ServerlessError: TimeoutError: Missing credentials in config

Related:
#1520
#1632
#1701
#1649

[DavidWells]

Sending people to read through https://docs.aws.amazon.com/cli/latest/userguide/cli-chap-getting-started.html#cli-config-files is a negative UX.

Lets remove this point of friction via:

• a setup step via the CLI
• and/or a GUI electron app

Either (or both) lets people plug in the AWS aws_access_key_id and aws_secret_access_key and writes it to their ~/.aws credentials file if the [default] block doesn't already exist.

[flomotlik]

We've fixed the error messages and added docs for setting up the AWS credentials properly. Imho this can be considered fixed at the moment. I don't think we should actively set up profiles ourselves and mess with AWS config files directly.