Modified R4D url to point to the new location for the R4D service.

The api for R4D has been changed. It used to be "http://linked-development.org", and new api is "http://api.linkeddev.swirrl.com/". This is a simple change to replace the previous api to show the research documents, if any, for a project.

The trello card for this change is: https://trello.com/c/140QAJjZ/308-8-modify-r4d-to-point-to-the-new-location-for-the-r4d-service