improve railway presets

* add preset for funiculars
* add preset for narrow gauge railways
* add gauge field to some railway presets
* add "electrified" field to some railway presets
fix geocode result classifications

use nominatim's "class" property instead of "type" for result
classifications when "type" is "yes". Happens for "bridge"s,
"tunnel"s, etc.
Added preset for veterinary