[WIP] Project Spiking

# Project Spiking
Add Project Spiking to Notification Plugins.

- [x] Move notification-plugins from js to coffee

## Email 
- [ ] Email

## Chat
- [x] Hipchat
- [x] Campfire
- [x] Flowdock
- [x] Hall
- [x] Jaconda
- [x] Slack

## Other
- [x] PagerDuty
- [x] Twilio
- [x] Webhook

Related: https://github.com/bugsnag/bugsnag-event-worker/pull/132