squashing in preparation for PR submission
cherry pick conflict correction: 1
cherry pick conflict correction: 1a
delete some left over commented code
deleting blanks lines
sync hints and hints_PR branches
sync changes from master that didn't somehow come over on rebase (?)
remove single quotes around drop down options string
correct item trimming to eliminate superfluous spaces
remove commented lines
correct single item checkbox logic
correct combination hint logic to work properly with multiple questions
Merge branch 'trbm/hints_PR' of https://github.com/edx/edx-platform into trbm/hints_PR

* 'trbm/hints_PR' of https://github.com/edx/edx-platform:
  correct combination hint logic to work properly with multiple questions
  correct single item checkbox logic
  remove commented lines
  remove single quotes around drop down options string correct item trimming to eliminate superfluous spaces
  sync changes from master that didn't somehow come over on rebase (?)
  sync hints and hints_PR branches
  deleting blanks lines
  delete some left over commented code
  cherry pick conflict correction: 1a
  cherry pick conflict correction: 1
  squashing in preparation for PR submission