[cloud] migrate ec2_asg to boto3 and support application ELB target g…

…roups. (#19667)

* switch to boto3 and add support for application ELBs with target groups.

* use py23 compatible dict iterator.

* removing commented out fail_json calls

utilize sets to simplify logic

remove setting a redundant variable

add bounds checking in two places

add AWSRetry decorator - do we want this for other functions too?

change xrange to range so python3 doesn't fail

remove sorting lists of dicts; in python2 this returns None, in python3 this fails

* remove error variable from traceback.format_exc

* Remove boto2-style calls brought in by rebase

Old boto-style calls to `as_group` attributes break in boto3

Also remove module from legacy-PEP8 list

* Add  parameter to target_group_arn option

* Fix HAS_BOTO3 check

* use tags.items() instead of iteritems

* import botocore

* Fixed bugs in deleting autoscaling groups

* make changes in deleting autoscaling groups pep8

* more pep8

* fix version

* fix bugs so local integration tests run

* fix launch config check

* reflect changed status for ASG updates

* Fix existing exception handling and use traceback.

Fix imports

* line length

* Fix notification setup

* Fix mutually exclusive arguments
Only one of the AvailabilityZones and VPCZoneIdentifier arguments should be provided to the CreateAutoScalingGroup call.

* Allow desired_capacity, min_size, max_size, launch_config_name to be derived from the existing ASG if not specified

Remove code updating dict after ASG already uses it