Updating bellows with new plugin factory fix.

Fixes major issue with plugin factory by using the updated factory function.

Status: **Ready to merge**

Reviewers: @donnielrt @Helen-Mobify @tedtate 
JIRA: https://mobify.atlassian.net/browse/CSOPS-573

## Changes
- Updated to use the new `Plugin.create` function

## How to test-drive this PR
- checkout this branch
- run `grunt test`
- upgrade a project that uses it, and make sure it works.