don't set the targeted-feedback attribute to 'always'
working toward a generalized parser for TF items
set aside changes for a moment while I figure out student answers....
checkbox TF working
checkboxes TF is working
Jeff's alwaysShowCorrectChoiceExplanation tag is not functional (because I reworked `do_targeted_feedback` and didn't know exactly how to implement it)
feedback title customization works (e.g., {{Very Good:Some dogs are brown}}

THIS BRANCH WILL STOP HERE WHILE WE DECIDE HOW TO HANDLE THE VARIOUS ISSUES