Add some indicator that a search is being processed.

[hohonuuli]

When a large search is run, the pages loads with an initial display of 0 results, which is updated as the results are returned. This can be confusing to users as it leaves them to believe the search has already completed. For large searchers, which may take a number of seconds to complete (i.e. forever to most internet users), this is especially confusing.

To remove the confusion, we can either add an indicator that results are loading, or maybe just change the label form 0 results to a label like running search, please be patient.

See #151 for an example of this issue in action.