[WIP] Two fixes related to making PHPCR-ODM work

- Changed requirements on routes to use .* to allow full paths
- Use ->find($id) instead of ->findBy(array('id' => $id)) which would
  never work with PHPCR-ODM

Relates to PR on core bundle: https://github.com/sonata-project/SonataCoreBundle/pull/82
i think we do the same for sonata admins, so it seems ok to me. not sure if we might open a security issue for the orm though - but can't think of an obvious one. the id `'; DROP TABLE media; --` should be escaped by sonata using the query builder i hope?