fixes #27 - consistency in the locator methods

Fixes #25: logs

* relied on `debug()` to log locator warnings
* moved logic to dedupe duplicates into its own method for better testing

Fixes #27: method deprecation:

    * listAllResources() -> getAllResources()
    * listBundleNames() -> getBundleNames()
Removing this means that not passing a filter results in `true` where before it used to result in `false`. Is that OK?