WFS from metadata

**Do not merge yet, please**

Someone can start a code review on this work. The metadata is not updated yet to use this new functionality so this shouldn't be merged for now. When the metadata is updated I will also do a bit more testing.
I know it's a bit unrelated, but I couldn't hold myself.

In OpenLayers now layers can be shuffled, the static order we have in step 3 can perhaps get out of order.