Adds the ability to preserve the feature IDs and properties when creating zonal stats without geojson

[doclements]

No description provided.

[perrygeo]

Thanks for the PR. Some changes suggested below.

[perrygeo]

Three suggestions for this section:

1. We can simplify the branching logic here

if preserve_properties and 'properties' in feat:
    ...

2. If the id is already part of properties, the preserve_ids implementation is superfluous. The true id, according to the GeoJSON spec, is at the top level of the feature.

if preserve_ids and 'id' in feat:
    feature_stats['id'] = feat['id']

3. Because this code deals with massaging the output data, not directly with zonal stats itself, I'd like to move it to the bottom of the function. This should share code with the application of geojson_out (geojson_out is basically equivalent to preserve_properties + preserve_ids + preserve_geometry)

[perrygeo]

Also, we'll need to add the new arguments to the function docstring.

[doclements]

github decided not to give any notifications for this so i've only just noticed the comments. I'll look into making the changes as discussed.

thanks