Meta-description for home page

At the moment Google is using the navigation as the description of our home page. 

![screenshot 2014-05-23 13 42 17](https://cloud.githubusercontent.com/assets/1784932/3066616/cd8c5a70-e277-11e3-935a-bd66fea12027.png)

Please can we add the meta-description tag in the header with the following text:

"A service which helps University of Cambridge researchers meet HEFCE and funder Open Access policy requirements."