• Changed expansion of semester codes to match University standard phrasing.

• Added support for teaching calendars that span multiple teaching periods: ...

– Added infosci:expand-period-code() function.
	– The global stylesheet variable $period-string is now set using infosci:expand-period-code().
	– Refactored output of calendar content (either as a LaTeX tabular or HTML table) into a callable template.

Fixed permissions.

- Split conditional processing, footnotes, document inclusion, LaTeX-specific ...

elements, maths, meta-elements, native code processing and Otago-specific
  elements into separate modules.
- Moved centering into basic text formatting module.