Use Galera cluster for the CMS database backend

[ericras]

Need to update modules so that db tables have primary keys

Full list of tables with no primary key:

• [x] exif_custom_mapped_fields, done inside /var/www/htdocs/sites/unl.edu.university-communications.digital-photo-archive/modules/
• [x] exif_custom_users,
• [x] form_builder_cache, 475eb66dcbe7dad44803b7d574b48075d6c47de1
• [x] forum_index, 5bb5eafcd10788fe65a926105fcf328629e7c8d6
• [x] honeypot_user, b9457d4926a75d8a2b9dd9a64397821f7c3bdeec
• [x] masquerade, 01a7e4b0c3cc3ce63695d1b2238e19453dbb5b98
• [x] taxonomy_index, 96de392ea680d417853bbe7d6d50b3a03d44d1be
• [x] workbench_moderation_transitions, 9b6bb2b23dc1698c9e15539e9be61803be98c4d9
• [x] wysiwyg_user dd874f040df1104637832fe3f972e50fa4eae97a

[ericras]

This is going to be the big one: Taxonomy: https://www.drupal.org/project/drupal/issues/610076

[ericras]

Taxonomy is going to need testing.

My inclination is to disable and remove Forum. It's enabled on a bunch of sites but I don't think any one has ever used it, in part because its not styled and kinda ugly.

[ericras]

Needs deployment still