commands/show: handle aliases
commands/show: handle aliases

Replace the ad-hoc get_plugin() function in the show command (which was
broken for aliases) with a call to pluginloader.get_plugin_class(),
which correctly handles alias resolution.

lisatn/workload-automation,setrofim/workload-automation,lisatn/workload-automation,setrofim/workload-automation,setrofim/workload-automation,lisatn/workload-automation,ARM-software/workload-automation,ARM-software/workload-automation,ARM-software/workload-automation,setrofim/workload-automation,ARM-software/workload-automation,lisatn/workload-automation