Adds adjustment of search term 'score' (Using in result ranking) so that
a relative 0.3 to 1.3 mulitplier is applied based upon relative
popularity within the whole database. At this point the term popularity
is still done via a prefix match against the search term.
Uses a SUM(IF(cond, a, IF(cond, a, ...))) chain to produce the scoring
result in the select query.