Add more fields to PlaceDetails class

[BenjiFarquhar]

In GoogleMapsPlaces.getDetailsByPlaceId, in the file lib/src/places.dart we can see that some places have a lot more fields than others, that are not in the PlaceDetails class, so cannot be captured (they are thrown away). Here is an image of an actual http response:

We should be able to capture all fields returned by the web request in PlaceDetails.

[BenjiFarquhar]

I've done a PR for this.

[luis901101]

Try with this google_maps_apis which is a fork of this package but with some improvements and bug fixes, including the PlaceDetails fields which are up to date with Google docs.