NIMAS and ePub mapping

[philbarker]

NIMAS baseline element set and ePub structural semantics both have useful structural metadata and strong accessibility (based on DAISY and WAI)

We should map OCX to these to make sure that we have accessibility covered and to provide export routes of OCX.

Example points to look for:

• frontmatter / bodymatter / endmatter structural elements may apply to courses as well as books
• document navigation in ePub
• ld (longdescription / longdesc) element / attribute