EPE-104 Closed WU tabs would periodically reappear

Fixes EPE-104

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
Merge pull request #158 from GordonSmith/EPE-104

EPE-104 Closed WU tabs would periodically reappear

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>