Add downloads on a per product basis. This includes seperating the additional content images, displayed for products like moment tensor, from the download links.
Fix double nested download section. In the scientific section, downloads are appended to end of content section.  The module footer is for the technical terms.
Add a mixed downloads and images output of ContentsXML data.
Remove reference to ContentsXML, it is no longer used.
Update tests.
Update ContentsXML.getDownloads method to not include header. Remove from ContentsXML.scss file also. Add header to each individual module and page where it is used.
Update toHtml to be private. It should only be called using the helper functions.
Readded hypocenter links to scientific summary page