Enhance logging around remove snapshot operations

Prior to removing a snapshot log the id, uid_ems, ems_ref, name, and
description to aid in diagnosing errors.

https://bugzilla.redhat.com/show_bug.cgi?id=1549299

app/models/vm_or_template/operations/snapshot.rb

@@ -63,6 +63,8 @@ def raw_remove_snapshot(snapshot_id)
     snapshot = snapshots.find_by(:id => snapshot_id)
     raise _("Requested VM snapshot not found, unable to remove snapshot") unless snapshot
     begin
+      _log.info("removing snapshot ID: [#{snapshot.id}] uid_ems: [#{snapshot.uid_ems}] ems_ref: [#{snapshot.ems_ref}] name: [#{snapshot.name}] description [#{snapshot.description}]")
+
       run_command_via_parent(:vm_remove_snapshot, :snMor => snapshot.uid_ems)
     rescue => err
       create_notification(:vm_snapshot_failure, :error => err.to_s, :snapshot_op => "remove")