Consider merging with ember-local-storage-decorator

This addon and [ember-local-storage-decorator](https://github.com/jelhan/ember-local-storage-decorator) seem to address the same use case. And even having a similar public API. Wondering if we should join forces and merge both. Time for open source is too limited to maintain two solutions for the same problem without good reasons in my opinion.

If not merging, we should at least document the differences helping (potential) users to decide which one to use. But I would prefer merging and sharing maintenance burden to be honest.