[Tagging] Deprecating of leisure=common and leisure=village_green

[Daniel Koć]

While making some cleaning in osm-carto we have found that 
leisure=common and leisure=village_green are probably not clear enough 
to show them any more. They both have deep roots in British law and 
history and are frequently misused, as far as I can tell.

Both are very popular - 57k and 86k uses, respectively - and still growing:

https://user-images.githubusercontent.com/5439713/33458839-19814f9c-d628-11e7-92fd-b51326fa8b25.png

That means that maybe such tagging should be discouraged and replaced to 
not spread the confusion.


-- 
"My method is uncertain/ It's a mess but it's working" [F. Apple]