JOSM pseudo classes

- [x] `:closed`: true for ways where the first node is the same as the last and for any multipolygon relation
- [ ] `:connection`: true for nodes that are used by more than one way
- [ ] `:unconnected`: true for nodes that are not used by any way
- [ ] `:tagged`: What JOSM considers tagged, i.e. an object that with a tag key other than the following: source*, source_ref, note, comment, converted_by, created_by, watch*, fixme, FIXME, description, attribution
- [ ] `:righthandtraffic`:  true if there is right-hand traffic at the current location
- [x] negate class, e.g. `!:tagged`

Will not support:
- `:new`: all new objects