Finish Lanes category and publish it

[plepe]

I already started a Lanes category in my test repository: https://www.openstreetbrowser.org/#categories=plepe/test/lanes

Finish that and move it to main.

Mentioned here:

• https://community.openstreetmap.org/t/josm-style-openstreetbrowser/7423/3

[plepe]

See also #60.