Bug 5369: Make series tracings use phrase indexes

Bug 5369: Make series tracings use phrase indexes

By definition, series tracings should search for other records in the same
series, i.e., those with the exact same series title. This patch forces the
tracings to use phrase indexes for series tracings.

Note that this patch DOES NOT respect TraceCompleteSubfields. While that may be
desirable, it is outside the scope of the current patch. An additional follow-up
patch could be written to add support for TraceCompleteSubfields, if community
concensus is that series tracings should obey TraceCompleteSubfields.

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Thx for the follow up and sign off Jared :)