Specifying which AWS credentials to use

Say I have multiple AWS accounts as reflected in my credentials file `~/.aws/credentials`:

```
[default]
aws_access_key_id = XXXX
aws_secret_access_key = XXXX

[foo]
aws_access_key_id = XXXX
aws_secret_access_key = XXXX

[bar]
aws_access_key_id = XXXX
aws_secret_access_key = XXXX

```

How can I tell `odo` which account to use?

The issue names the AWS credentials file at ~/.aws/credentials but does not identify implementation files or tests. Start by locating odo's AWS credential-loading entry point and determine how a named profile could be selected. Done should allow the user to choose among the listed AWS accounts and verify that the selected credentials are used.

Written by the indexing model from the issue text.