Curator UI proposal: Add "drag and drop"-functionality

[Kigaard]

As a curator, it can be a tedious task to rearrange entries in "Links", if a nice ordering is wanted. For example if two links to a GitHub repository is already added, but you want to add the issue tracker under the relevant repository, it could quickly involve into copy/paste/deleting to get the ideal ordering.

Such "drag and drop"-functionality could also be added for Functions, Topics (Label), Links (as mentioned), Downloads, Documentation, Publications, Credit & Support.

-Mads