Network type "walk" should consider extra relationships

[fabmazz]

Contributing guidelines

• I understand the contributing guidelines

Documentation

• My proposal is not addressed by the documentation or examples

Existing issues

• Nothing similar appears in an existing issue

What problem does your feature proposal solve?

I have to download the walking path of a city, and by looking at the network downloaded with 'G = osmnx.graph_from_bbox(BBOX,network_type="walk", simplify=False)`, there are some crossing missings, so that two sides of a road are isolated for hundreds of meters.

What is your proposed solution?

I've looked at the OSM, and in fact the crossing are marked as "bycicle paths", but a special tag is assigned to them to show they are both bicycle and pedestrian crossings.

I think the library in the case of the walking path should download the paths tagged with "foot"="designated" (see the screenshot and the OSM documentation.

What alternatives have you considered?

Nothing

Additional context

By adding the tag ["foot"="designated"] to the filter manually, it's possible to also download these crossings.

[gboeing]

Thanks for suggesting this. Would you like to open a PR and I can take a look?

[gboeing]

@fabmazz are you interested in proposing a pull request?