[Tagging] Marking climbing proposal as "in use"

[Richard]

Hi,

http://wiki.openstreetmap.org/wiki/Proposed_features/Climbing

was sitting around and evolving for 8 years. If there are no 
objections I would promote its status to "in use".

Afaics it has never attracted significant controversy, does not
trigger any technical difficulties, there is demand for it and 
is well used considering that it is a domain relevant only for
a minor fraction of mappers.

Richard