DATACASS-150: Move to Asciidoctor for reference documentation

First cut at porting the existing docbook reference documentation to asciidoctor.
Merge commit 'c05c3630dfe258f7e527b03c215a0e3fca37e5db'

* commit 'c05c3630dfe258f7e527b03c215a0e3fca37e5db':
  DATACASS-150: Move to Asciidoctor for reference documentation