UP-4142 Importing local group changes updates cached entries

https://issues.jasig.org/browse/UP-4142

Also shows failed data import from Admin UI in red to make it more clear a failure occurred.

I have not yet been able to test in a clustered uPortal environment, but this change works in a single node.  An ant initdb yields correct group and membership information for groups of people and portlets.  Am submitting change to get reviewed and into code base.  I will test clustered scenario and submit update if it doesn't work (code comments suggest it will work, just can't get hsql db server to accept connections from another machine to test).
If it were necessary, I would hope that the individual who put it there and (presumably) knew why it was necessary would include a not about it.  It's nice to improve code when we see a clear opportunity.