WebSearch: no special behaviour for subject index

• FIX Removes special behaviour of the "subject" index that was hard-coded based on the index name. Installations should rather specify wanted behaviour by means of configurable tokeniser instead.

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
Reviewed-by: Jan Aage Lavik <jan.age.lavik@cern.ch>