Update to name reflecting age of style

The University of Leeds has amended it's Harvard style. Students using this style via e.g. Mendeley need to be aware that the style is out of date.
Hopefully I'll get a chance to look at what we changed in August 2013 and add an up-to-date CSL at some point.
Merge pull request #811 from jesusbagpuss/patch-1

Update to name reflecting age of style