Expand the AssessmentItemCategory entity to include “Multiple-choice multi-select”

Multiple choice, multi-select is the second most common item type after plain “multiple choice.” We’d suggest adding “Multiple-choice multi-select” to the available categories: http://schema.ed-fi.org/datahandbook-rfc14/MetaEd-Handbook-Index.html#/AssessmentItemCategory130

While this may be considered a sub-type of multiple choice, most providers code and market it as a separate type.  An alternative would be to have an additional sub-parameter to note that the answer type is “many” versus “one.” This is important both functionally a visually; even if there is only one correct answer, a MCMS shows checkboxes instead of radio buttons and allows for the selection of multiple answers.