SolrUtils: support high count of logical clauses

* Needed for ranking of records.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
SolrUtils: cleaner schema.xml

* Allows only one value per field.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
SolrUtils: support entire full-text indexing

* Indexes entire possibly long documents.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
BibRank: index latest records first in Solr

* Allows the ranker to return better results during long
  indexing runs.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
BibRank: new multi-tag Solr indexer

* Allows to index multiple tags per Solr field
  by using logical fields.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
BibRank: faster Solr indexer

* Reduces count of commits.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
BibRank: better Solr regression tests

* Fixes regression tests for richer indexes.

* Adds tests for indexing of logical fields.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
BibFormat: fix for snippet generation

* Uses CFG_WEBSEARCH_FULLTEXT_SNIPPETS, the correct config
  variable, for maximum amount of snippets.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
SolrUtils: faster snippet factility

* Makes use of FastVectorHighlighter.

* Backward-compatible to old indexes.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>
SolrUtils: better exception handling in indexers

* Improves exception handling for add and commit calls.

* Makes use of autocommit in case commit could not be
  performed.

Signed-off-by: Patrick Glauner <patrick.oliver.glauner@cern.ch>
Tested-by: Tibor Simko <tibor.simko@cern.ch>