Support for Auto Scaling Group Tags

This enhancement provides the ability to create and edit tags for Auto Scaling Groups.  Specific functionality is to add tags on ASG creation, add/edit/delete tags on existing ASG's, add/edit/delete tags on sequential ASG's, and view tags on rolling ASG's.

Client side validation is done to ensure tags and values are unique, and there are no more than 10 tags per ASG.

This feature satisfies feature request #219