Revised XMLEventStreamWriter to allow for empty elements with attributes

Issue: SPR-11254
(cherry picked from commit ee5b7fd)
Polishing

Issue: SPR-11254
(cherry picked from commit 9a39f39)
ResourceDatabasePopulator's setScripts takes varargs
(cherry picked from commit e3017c3)
@Enable registrars called with correct metadata when placed on superclass

Issue: SPR-11251
Polishing around @Enable processing and @EnableTransactionManagement

Issue: SPR-11251