Take advantage of Dismax parser on advanced search screen

Up to version 1.1 of VuFind, all advanced searches are processed into Lucene queries through tokenization and munging. This process relies on "OR" queries to catch outliers, which results in inflated result set sizes. There are also some edge cases where valid query results may be missed.

Fortunately, Solr provides a special pseudofield called _query_ which can be used to embed other types of queries within a Lucene query. This can be used to combine multiple Dismax queries together. This feature should be added to the advanced search processing code to reduce reliance on our less-than-ideal Lucene query generation logic.