Improve fuzzy query performance

    This reorders the columns in the primary fuzzy index in order to
    allow it to be used more effectively.  Because the tuvCount
    portions of the fuzzy query were using range queries, the query
    is unable to use the remaining index columns.  This change moves the
    tuvCount column in the index to the last position.  This increases
    the effective key length of the index (via EXPLAIN) from 10 to
    17 bits, and has been observed to improve fuzzy query performance
    by ~5x.