- drop index tables which are not used anymore (at end of indexing)
e.g. webpac-hidra link_900
+
++ give useful error message when results are not found
+
+- add support for transcripts of a,o,u umlauts (ae ou ue)
+ a -> (a|ae)
+
+- remove dependency on HTML::Parser (HTML::Entities used in index_DBI_cache)