… for tag propagation, proagate default tags to instances, allow propagated name to be set independently of ASG

- Add additional attributes that have been added to the launch template specification lately
- Remove the null resource for updating propagated tags; replace with a list comprehension expression that achieves the same result
- Add default tags data source and add in default tags to propagated tags: closes #162
- Add new variable `instance_name` that allows users to set the propagated instance name independently of the ASG `var.name`; if not specified it defaults to current `var.name`: closes #158
- Make the attribute `block_duration_minutes` option under `spot_options` - this is still supported in the AWS provider but by making this optional it will fix/close #156

Co-authored-by: Anton Babenko <[email protected]>

Co-authored-by: Anton Babenko <[email protected]>