* Finished first cut of managed node groups
* Updated formatting and extra fields.
* Updating Changelog and README
* Fixing formatting
* Fixing docs.
* Updating required Version
* Updating changelog
* Adding example for managed node groups
* Managed IAM Roles for Nodegroups now have correct policies. Tags can now be added to node groups.
* Fixing bug where people could set source_security_group_ids without setting ssh key causing a race condition within the aws provider.
* Adding lifecycle create_before_destroy
* Adding random pet names for create_before_destroy
* Updating per comments.
* Updating required versions of terraform
* Updating per comments.
* Updating vars
* Updating minimum version for terraform
* Change worker_groups_managed_node_groups to node_groups
* Using for_each on the random_pet
* Adding changes recommended by @eytanhanig
* Update node_groups.tf
* run terraform upgrade tool
* fix post upgrade TODOs
* use strict typing for variables
* upgrade examples, point them at VPC module tf 0.12 PR
* remove unnecessary `coalesce()` calls
coalesce(lookup(map, key, ""), default) -> lookup(map, key, default)
* Fix autoscaling_enabled broken (#1)
* always set a value for tags, fix coalescelist calls
* always set a value for these tags
* fix tag value
* fix tag value
* default element available
* added default value
* added a general default
without this default - TF is throwing an error when running a destroy
* Fix CI
* Change vpc module back to `terraform-aws-modules/vpc/aws` in example
* Update CHANGELOG.md
* Change type of variable `cluster_log_retention_in_days` to number
* Remove `xx_count` variables
* Actual lists instead of strings with commas
* Remove `xx_count` variable from docs
* Replace element with list indexing
* Change variable `worker_group_tags` to a attribute of worker_group
* Fix workers_launch_template_mixed tags
* Change override_instance_type_x variables to list.
* Update CHANGELOG.md
