Support options for segment adapter

[ryanlabouve]

The segment trackEvent supports an extra options argument. https://segment.com/docs/sources/website/analytics.js/#track

I'd love some way to support this in the segment adapter.

In the meantime I've done something like this in the app where I need it:

import SegmentAdapter from 'ember-metrics/metrics-adapters/segment';
import canUseDOM from 'ember-metrics/utils/can-use-dom';
import { compact } from 'ember-metrics/utils/object-transforms';

export default SegmentAdapter.extend({
  toStringExtension() {
    return 'segment-extended';
  },

  trackEvent(options = {}) {
    const compactedOptions = compact(options);
    const { event, segmentOptions } = compactedOptions;

    delete compactedOptions.event;
    delete compactedOptions.segmentOptions;

    if (canUseDOM) {
      window.analytics.track(event, compactedOptions, segmentOptions);
    }
  }
});

I'd be happy to add tests and do something like this in the current Segment adapter.