Create university-of-south-australia-harvard-2013.csl

The 2013 revision of the UniSA style guide. Derived and revamped from the 2011 csl. A few notable changes:
- Subsequent author substitution by a dash in the bibliography listing.
- Director label for motion pictures.
- Online audio recordings use "accessed" instead of "viewed".
Update university-of-south-australia-harvard-2013.csl

Non-CSL term "thesis" was removed.
Merge pull request #582 from Luboszot/patch-3

Create university-of-south-australia-harvard-2013.csl