feature/022-disabe-add-to-dashboard-button

Purpose
-----------
Prevent multiple clicks from submitting requests before the first request has finished.

Changes
------------
Disable the link upon clicking the button, and re-enable only on successful completion of the change.

Modify error messages to be more descriptive.

Add explicit Raven logging for errors.

Side effects
----------------
If the request fails, inform the user that they need to reload to re-enable the functionality and keep the button disabled. Re-enable when the button