Bug 8208: Add fast-add link to auth finder plugin

Bug 8208: Add fast-add link to auth finder plugin

When performing subject analysis, it is not uncommon to find that an
authority record you need does not exist. This commit adds a link in
the search results to enable the cataloger to create an authority on
the fly and have the heading populated by the new authority.

To test:
1. Use the auth finder plugin the cataloguing module to search for a
   heading you do not have an authority record for.
2. Click the "Create new" link.
3. Fill in your authority and save it.
4. Note that the heading field was populated with the data you entered
   in the authority record.

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
1) Added a new authority using the plugin
2) Used an existing authority using the plugin
3) Created a new authority in the authority module

All worked nicely.