Support for EC2 backups

[neovasili]

Create a new feature that adds support to create backups of EC2 volumes or creating AMIs of instances using the attached tags to the instance.
Consider the following tags:

• backup: [ 'snapshots', 'ami' ] --> if backup is snapshots or ami based
• retention: number of days that backups may be retained in time

Backup process will fail if not both tags exists and both have valid values.