MBS-5644: Added release relationships editor button to link checked recordings to work

This is going to be important for linking to books, as required by the new audiobook style guideline. The original ticket also gave linking recordings on a "single" release as a use case.

I added a button in the relationship editor template, at the top of the page with the other batch buttons. Then I added a new type of dialog, "BatchLinkWorksDialog". I based this partly on the existing "BatchCreateWorksDialog", but removed the specializations needed there.

Also added the required click js.

My first assigned improvement, so please let me know if there's any better way of doing what I've done. This change is live and working at http://lordsputnik.mbsandbox.org/