Worker group tags (#252)

* Allow per worker group ASG tags to be set

* Format

* Set correct defaults

* Implement hack that will use the first item in the list if a matching item does not exist for the worker group

* Use a map that will map from the worker group name to the tags to get around the issue where list indexing does not work with a list of lists

* Format

* Cleanup

* Fix sample

* README

examples/eks_test_fixture/main.tf

@@ -39,6 +39,26 @@ locals {
   #   },
   # ]
 
+
+  # the commented out worker group tags below shows an example of how to define
+  # custom tags for the worker groups ASG
+  # worker_group_tags = {
+  #   worker_group_a = [
+  #     {
+  #       key                 = "k8s.io/cluster-autoscaler/node-template/taint/nvidia.com/gpu"
+  #       value               = "gpu:NoSchedule"
+  #       propagate_at_launch = true
+  #     },
+  #   ],
+  #   worker_group_b = [
+  #     {
+  #       key                 = "k8s.io/cluster-autoscaler/node-template/taint/nvidia.com/gpu"
+  #       value               = "gpu:NoSchedule"
+  #       propagate_at_launch = true
+  #     },
+  #   ],
+  # }
+
   worker_groups = [
     {
       # This will launch an autoscaling group with only On-Demand instances