[Tagging] improve tagging of traffic_calming

[Martin Koppenhoefer]

sent from a phone

> Am 21.11.2015 um 17:07 schrieb Gerd Petermann <gpetermann_muenchen at hotmail.com>:
> 
> As I said, I have no problem with them. The important part is 
> that you don't cut e.g. a highway=secondary into small fragments with
> alternating highway=traffic_calming,highway=secondary,
> highway=traffic_calming,
> highway=secondary, ...


I also believe we should deprecate using the highway key for traffic calming and instead suggest to use traffic_calming

cheers 
Martin