The assessments table now completes the last row

EV-112

iText requires that a row be complete to render. That means
that if a row does not have as many cells as it expects, then
that row will not render. I have added a bit of code that completes
the row.
Made requested changes from last commit

EV-112
Merge pull request #15 from osu-mist/feature/EV112-pdf-criteria

The assessments table now completes the last row