- Reduces the chance of problems caused by slow Solr download during "composer install"

- The cache is automatically refreshed if the information on any of the actual MyResearch pages doesn't match the cached status.

This can be accomplished by adding clear_demo=1 parameter to any VuFind url that uses the Demo driver.

- Made session expiration check behavior configurable
- Added support / config setting for reading Shibboleth attributes via headers
- Added support for multiple IdPs (useful in a MultiBackend setup)
- Significant code refactoring/improvement.

- It might not be if it's missing from HMACKeys.

Also adds check for INACTIVE sub.