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 do not know if this would break the `/{format}` parameter.

@dbu @rande what do you think this is OK, or should we URL encode (and decode) the path? Or use the UUID ?