Show exclusions count as separate from deletions count.
When there is an error on the Ajax call, display the error status and stop asking for refreshes.
When a rebuild is requested, redirect to just status, so refreshing the page would not request another rebuild.
Create a bridge implementation of SearchIndexerImpl that just wraps around an old IndexBuilder.
Modify client code:
Application, BasicAuthenticator, SearchServiceController, SparqlUpdateApiController,
UpdateUrisInIndex and VClassGroupCache
Rewrite IndexController to use AJAX and to show the current status and history of the indexer events.
