[Tagging] cave_entrance. ref and name

[Richard]

On Mon, Aug 29, 2016 at 05:20:19PM +0200, Martin Koppenhoefer wrote:
> 
> 
> sent from a phone
> 
> > Il giorno 29 ago 2016, alle ore 12:24, Richard <ricoz.osm at gmail.com> ha scritto:
> > 
> > are you saying we should use "cave:ref" just to avoid the use of a relation?
> 
> 
> according to the wiki, that's the standard fag to add to a cave entrance for referring to the cave ref

added that to the description, the docs still need tweaking. 
German cave_entrance description lacks any mention of "cave:ref". 
The english says "number in a cave cadastre" which is perhaps 
a remnant of French translation and not terribly useful as it 
would imply an official registry which may exist only in few
countries.

So what does cave:ref really mean? Should that say something like 
"unique cave identifier"?
Shouldn't cave:ref be subtyped for example as "cave:ref:at" or
"cave:ref:fr" for austrian resp french ids to prevent id clashes?

Richard