Don't remove the body tag when only Mathjax is present.
Don't remove the body tag when only Mathjax is present.

Handle Mathjax separately when it is the only thing in the editor. If
there is only a Mathjax equation then instead of deleting the div that
contains them, we delete all the nodes inside the div and leave the div
alone.

StileEducation/Squire,StileEducation/Squire