Removes `renameKey` from options

Namespacing bug fix.

Adds basic JSON loader, `isRegistered` check

Fixes a bug with path resolution, minor updates

use `set-value` to directly set on the data object so we don't emit `…

…set` when adding data, and move emit to the top of the data method so we can avoid absure normalization logic for consistently emitting args

exposes data and options to custom namespace/rename functions

ensure that object exists when custom property is defined.

change to plugin signature so it can be registered with `use`