Feature request: Add a command to login to ECR with ease

[apurandare-aurva]

First of all, I want to say thank you for creating this tool, it is great and solves the annoying problem of AWS CLI commands.

As I have been using it everyday, it tends to handle my workflows really well with the automatic re-authentication turned on as well.

The one workflow with ECR I find annoying is the login, every time to pull a container image, I run this command: aws ecr get-login-password --region <region> | docker login --username AWS --password-stdin <account-number>.dkr.ecr.<region>.amazonaws.com (and I along with many of my colleagues have tried the https://github.com/awslabs/amazon-ecr-credential-helper and it is not useful when logging into many accounts from dev to staging to production).

It'd be great if we can have a command that simplifies this use-case. Thank you for considering this