To illustrate why I've asked for `return this;`... 

```js
// Add a new draft and update data store
Drafts.add(draft).store();

// Delete a draft and update data store
Drafts.delete(draft).store();

// Eliminate all drafts and update data store
Drafts.clear().store();
```

Which is nicer than:

```js
// Add a new draft and update data store
Drafts.add(draft);
Drafts.store();

// Delete a draft and update data store
Drafts.delete(draft);
Drafts.store();

// Eliminate all drafts and update data store
Drafts.clear();
Drafts.store();
```