WebSearch: fix for snippet highlighting

* Highlights terms that are only searched in fulltext.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
WebLinkback: faster email notification

 * Improves database layer to send email notification faster

 * Extends regression tests for this improvement

 * Applies minor clean-up
WebLinkback: faster deletion of linkbacks on blacklist

 * Avoids redundant creations of blacklist
WebSearch: new parsing of unbalanced phrase queries

* Removes unbalanced double quotation marks.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
WebSearch: new fulltext by default search

 * Adds checkbox to search terms also in to fulltext to the add
   to search interface.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
BibRank: Solr: better ranking for fulltext by default

 * Ranks fulltext and metadata properly

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
BibRecord: new MARC code filter

* Filters a record based on MARC code

* Supports wildcards in identifiers and subfield code

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
BibFormat: new 'xmf' format

* Supports filtering per MARC tag, identifier and subfield

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>