Add Trips, device id

[corypisano]

Adds:

• Trips! (startTrip, updateTrip, completeTrip, cancelTrip, and adds tripOptions to trackOnce)
• set custom headers
• set device id
• option to set custom track endpoint

Story details: https://app.clubhouse.io/radarlabs/story/6419

[shortcut-integration[bot]]

This pull request has been linked to Clubhouse Story #6419: Update JS-SDK: Trips & Mock Tracking.

[kochis]

You should also bump the version file (to match what's published):

src: https://github.com/radarlabs/radar-sdk-js/blob/master/src/version.js package.json: https://github.com/radarlabs/radar-sdk-js/blob/master/package.json#L6