Error description in the Sierra REST API is optional, while name is not, so fall back to name if there's no description. Also use empty() instead if isset() to avoid considering code 0 an error.

A block of HTML is copied to make a template; some of the id elements were being
removed, but 2 were left on causing Lighthouse to complain about
duplicate ids.

SortSite flags "Strong" as invalid markup that could trip up
a screen reader.

- Improves OAI-PMH validation.

- Resolves VUFIND-1294.

- Includes Alma-specific authentication module and controller for handling webhooks.
- Resolves VUFIND-1212.

- Resolves VUFIND-1275.

- Zend Framework 2 references are out of date; using an external library location no longer makes sense.