Added Event Subscriber

- Easily extend gush
Merge pull request #1 from dantleech/event_dispatcher

This PR was merged into dantleech:master branch.

Discussion
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Test

                        
| Q             | A    |
| ---           | ---  |
| Bug fix?      | y    |
| New feature?  | n    |
| BC breaks?    | n    |
| Deprecations? | n    |
| Tests pass?   | y    |
| Fixed tickets | #000 |
| License       | MIT  |
| Doc PR        |      |
                        


Commits
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b5e6acdc48b33c8cfa03e73d8eddbc9720e73f47 Added Event Subscriber

- Easily extend gush dantleech