Add a open command

[jaydhulia]

• Added a open command that generates a deep ConsoleMe link, given an ARN
• As ConsoleMe adds support for more resources, weep won't need to be updated and will auto-add support for those resources
• Where ConsoleMe supports it (IAM Role, S3, SNS, SQS), the link will open to ConsoleMe's editor. Where ConsoleMe doesn't support that resource directly, it will try to redirect to the AWS Console with the right role through ConsoleMe
• By default, open will open the browser, but this can be changed by including a flag

[patricksanders]

I like what you've done here! The one hesitation I have here is the command name in relation to its default behavior. I think we should make weep link output a link (to be used for sharing, etc) and add a weep console command that opens the link in a browser. This second command will also be used for opening a console for a requested role.

[patricksanders]

We should define a type for this response instead of using map[string]string here

[patricksanders]

LGTM