Add capacity to playground:swing-preset
Add capacity to playground:swing-preset

The capacity defines if there is one swing on the object or more. A lot of playgrounds have one structure with two swings on it.
AndreasHae/iD,AndreasHae/iD,kartta-labs/iD,AndreasHae/iD,openstreetmap/iD,openstreetmap/iD,digidem/iD,kartta-labs/iD,digidem/iD,kartta-labs/iD,ngageoint/hootenanny-ui,ngageoint/hootenanny-ui,ngageoint/hootenanny-ui,openstreetmap/iD,morray/iD,morray/iD