Watch student count instead of iframe_holder
Watch student count instead of iframe_holder

Canvas optimized some of their writes so that the iframe_holder is no longer updated every time you move to the next student. Instead, watch x_of_x_student_frd for changes instead.
Added a separate Mutation Observer on iframe_holder to see when content has loaded
All non-quiz content inside SpeedGrader is now throwing a cross-domain error, not just external sources like Turtitin.
Fixed indentation (so this looks like a huge change unless you ignore whitespace)
mfishtrom/seqcanvas,jamesjonesmath/canvancement,jamesjonesmath/canvancement,jamesjonesmath/canvancement,mfishtrom/seqcanvas,jamesjonesmath/canvancement,mfishtrom/seqcanvas,jamesjonesmath/canvancement,mfishtrom/seqcanvas,mfishtrom/seqcanvas