Improving path and URL for segment.io in Hashbang mode

My app is in hashbang mode right now. I noticed all the paths in segment.io (& GA indirectly) were being reported as `/`, with the "name" `/user/12345`. This fix manually sets the `url` and `path` properties when the page view is sent to Segment.

A couple of things to note about this PR:
1. It adds `$location` to the call to `trackPageView`. On the one hand, this is a fairly far reaching change, but on the other it makes total sense. It seems reasonable that a plugin should have access to the `$location` object when tracking page views.
2. The `name` property is no longer set on the call to segment. This might be a problem to people that are relying on that functionality (although it is a little inaccurate since it was always being set to the path, which is not the intended use case for the `name` property in segment - for example, check out [this side effect of passing a name](https://segment.com/docs/integrations/amplitude/?utm_source=amplitude.com&utm_medium=partner-website&utm_content=generic-docs&utm_campaign=docs#page))

Note I did try something like:

```
  $analyticsProvider.registerPageTrack(function (path, $location) {
    $injector.invoke(['$location',function($location) {
      try {
          analytics.page({
            path: path,
            url: $location.absUrl()
          });
      } catch (e) {
          if (!(e instanceof ReferenceError)) {
              throw e;
          }
      }
    }]);
  });
```

but it was unable to resolve the `$location` service for some reason. Due to time constraints, I took a simpler path.