Support deleting all Splunk artifacts owned by the logged in user

[regimus]

Currently any Splunk artifacts deleted in the local repository doesn't also get removed from the Splunk server. This means that we will accumulate more and more orphans over time.

One solution to this, if a service account is used, is to update the Pickaxe tool to clear out any Splunk artifacts owned by the service account, before the tool uploads everything.

[bbaugher]

I think this could definitely help. The change is likely not small or trivial though