Merge the DAO refactor branch

- move DAO APIs into opennms-dao-api
- create new mock DAOs in opennms-dao-mock
- create a new test context that is a drop-in
  replacement for applicationContext-dao.xml
  (applicationContext-mockDao.xml)
- create a new test context that creates a
  mock event daemon (applicationContext-mockEventd.xml)
- update many tests to use the new mock DAOs
- update many tests to use the minimalist event
  and collection configs
- many other small tweaks and cleanups