Stop creating the place_classtype tables from special phrases

Stop creating the place_classtype tables from special phrases

The special phrase import created one table per class/type pair, indexed
it on centroid and place_id and granted the webuser access to it. Nothing
reads those tables anymore, so all of that goes. What is left is
collecting the phrases and handing them to the tokenizer.

The --min option only decided which of the tables were created, it never
filtered the phrases themselves, so it has no meaning without them. It is
removed together with get_classtype_pairs().

The table counters in the statistics handler would report zero forever.