Add toilet POI icon for marking bathrooms/restrooms/toilets

[Pengor]

Adds a POI for toilets 🚽 I just realized this POI was missing so I thought I'd take a swing at it:

I figured the infrastructure color made the most sense, but I'm certainly open to changing that. I first attempted a side-view of a toilet as the icon and then a 45° angle view (semi-3D) but neither turned out very well in my opinion.