Public API and trigger events

- Public methods for retrieving and setting the view id
- Public method for checking if picker is open/visible
- Trigger "open" when picker is visible
- Trigger "picked" when the action is picked and providing the response documents as a param
- Trigger "cancel" when the action is cancel

Fix url origin when testing locally

- Checking value of document.referrer to determine how to configure origin value
- Extract just domain from document.referrer value
- Leveraging window.location to assign value to origin when no document.referrer value
Merge pull request #6 from stulees/master

Public API and trigger events