Change Default Path Repository Cache Behavior to Not Cache

The path repositories currently have a default cache policy that caches nodes for 30 seconds. In previous releases, nothing was cached. The default cache policy should be to not cache anything both for backwards compatibility and to avoid confusing evaluators who won't understand why there's a 30 second delay between them directly adding a file or folder to an FS repository source and the corresponding node showing up in the JCR repository.