Listing and Deletion of Alias from an invalid Cluster name, returns successful message to the user.

Listing and Deletion of Alias from an invalid Cluster name , returns successful message to the user .

Scenario1 :
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Step 1: Created Alias "alias1" in cluster "cluster1"
Step 2: Deleted Alias "alias1" from cluster "cluster2" (cluster2 does not have alias1)

omm@XXXXXXXX:/home/Knox/knox-0.6.0-SNAPSHOT/bin> ./knoxcli.sh delete-alias alias1 --cluster cluster2
alias1 has been successfully deleted.

Scenario 2:
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Step 1: Created Alias "alias1" in cluster "cluster1"
Step 2: Listed Alias "cluster2" (which is not available)

omm@XXXXXXXX:/home/Knox/knox-0.6.0-SNAPSHOT/bin> ./knoxcli.sh list-alias --cluster cluster2
Listing aliases for: cluster2

0 items.