Clean up variables list command output

[Baggerone]

variables list -v idphelp -o abcd probably doesn't need to output the workspaces that have no match.

In other words, don't output the lines that say foo has no matching variables.

Also, for found matches, output the workspace name on the same line as the variable information.

[briskt]

@fillup there are two separate things suggested here. I think the PR only addresses the first. Was the other fixed in a separate PR?