Include warning about limited results on search page

In the search page, users can only browse up to 10.000 results. The interface could be clearer that the "last page" does not actually contain the final results.

Suggestion: show a warning message if you visit page 500 and there are more than 10.000 results total. E.g. "Your query has X results, but only the first 10.000 results can be browsed on Textcavator."

Start at the search page and trace how pagination handles page 500 and the total result count. Done means showing a warning there when more than 10,000 results exist, explaining that only the first 10,000 can be browsed.

Written by the indexing model from the issue text.