Adding support for the AWS_CLUSTER_NAME env variable allowing to claim volumes ownership

Signed-off-by: Lukasz Jakimczuk <ljakimczuk@gmail.com>

Moving check for environment variable outside the loop

Signed-off-by: Lukasz Jakimczuk <ljakimczuk@gmail.com>

Insert a note about AWS_CLUSTER_NAME in the aws-config doc

Signed-off-by: Lukasz Jakimczuk <ljakimczuk@gmail.com>

Improving implementation and documentation

Signed-off-by: Lukasz Jakimczuk <ljakimczuk@gmail.com>

Changing instructions, adding unit test for getTagsForCluster and removing duplicated Lookup

Signed-off-by: Lukasz Jakimczuk <ljakimczuk@gmail.com>

Commit after update

Signed-off-by: Lukasz Jakimczuk <ljakimczuk@gmail.com>

Correcting bad formatting in aws-config.md

Signed-off-by: Lukasz Jakimczuk <ljakimczuk@gmail.com>

examples/aws/10-deployment.yaml

@@ -50,6 +50,8 @@ spec:
               value: /credentials/cloud
             - name: ARK_SCRATCH_DIR
               value: /scratch
+            #- name: AWS_CLUSTER_NAME
+            #  value: <YOUR_CLUSTER_NAME>
       volumes:
         - name: cloud-credentials
           secret:
@@ -57,4 +59,4 @@ spec:
         - name: plugins
           emptyDir: {}
         - name: scratch
-          emptyDir: {}
+          emptyDir: {}