updated native types and providers to use base_path/config when puppet is run under nonroot user

  * this is needed because if sensu is run with a nonroot user
    the config files cannot be used as they are owned by root
    thus puppet cannot conigure what it does not have access to.

  * This is part 1 of what needs to be changed, since this sets
    defaults for base_path we can add this ability now and work
    on the manifests to be nonroot compliant later.