WIP: Add config

Closes #3184189

config/install/select2_all.settings.yml

+enable_front_admin: both
+selector_global: 'select:visible'
+selector_optin: 'select.select2-enable'
+selector_optout: '#field-ui-field-storage-add-form select, #entity-form-display-edit-form select, #entity-view-display-edit-form select, .wysiwyg, .draggable select[name$="[weight]"], .draggable select[name$="[position]"], .locale-translate-filter-form select, .select2-disable, .select2-processed'
+minimum_single: 10
+minimum_multiple: 5
+options:
+  minimum_results_for_search: 0
+  width: 'resolve'