mongodb and spring: so much magic

- Ripped out a lot of things that aren't needed
- Database access is through spring Repository abstraction
- PageController added to server our initial simple use cases
- Simple index.html added, is given all "Entry" objects in the db
  and crudely displays them
- ApplicationConfig added, where mongo config can be stored (better name
  later)
- No testing (this is bad!  Need to learn how to test with spring
  dependency injection)