Improve speed of workflow model listing

The query used to list all (filtered) route models is (DOC_ROUTING_SEARCH_ALL_ROUTE_MODELS):

SELECT * FROM DocumentRoute WHERE ecm:currentLifeCycleState = 'validated' AND dc:title LIKE '%'

This is very inefficient and the LIKE (which is here because the same query is used in other cases to do a prefix search) should be removed.