Added > /dev/null tags to the commands which run tex and dvi for
HTML_img mode. These will probably work now for the most part.
I don't know how well this will work if there is an error in
getting either tex or dvips to run.
For many problems using WeBWorK1.8 and typeset3 mode thing work fine.
Please submit example problems where the images don't show up or some
other image related error occurs as bugs to