Fixing abox.py multichoice type to allow comma in expect string, typo
Fixing abox.py multichoice type to allow comma in expect string, typo

jefrench/latex2edx,evheubel/latex2edx,jefrench/latex2edx,mitocw/latex2edx,evheubel/latex2edx,evheubel/latex2edx,mitocw/latex2edx,jefrench/latex2edx,mitocw/latex2edx