Add resource name utils

Resource names work well as split up prefixes and identifiers as we've done it in woocommerce-admin. It makes sense to add these small utility functions into fresh-data itself.

https://github.com/woocommerce/woocommerce-admin/blob/master/client/wc-api/utils.js

Start by reading the referenced woocommerce-admin client/wc-api/utils.js implementation and then inspect fresh-data's existing utility structure. Identify the resource-name prefix and identifier helpers that should be brought into fresh-data; done means the corresponding utilities are available there with behavior matching the reference.

Written by the indexing model from the issue text.