Add example for OR condition in custom filter

[EwoutH]

I would be curious on how to do more advanced custom filters, for example how to combine two (in and OR fasion).

custom_filter = '["highway"~"motorway|motorway_link"]'
construction_filter = '["construction"~"motorway|motorway_link"]'
full_filter = ???

Possible syntax and examples of more advanced custom filter could be added to 08-custom-filters-infrastructure.ipynb