moved blanks-vetting code to totes; made it operate exclusively on total lines;
fixes #13

changed the bit-shuffling in the totes vetting code to operate past the
"trivial" blanks, i.e. start at the first non-blank column that follows the
"Total" column; fixes #14

avoiding the column quantity vetting for totes; we don't care about strings,
just nonblanks; this means that we don't care about trailing "NA" and "--";
fixes #15
fixed #12 : tolerating pre-totes blank lines