[talk-au] Mapping planned light rail routes

[stevea]

To be clear, "infrastructure" tagging as I described it doesn't necessarily come first, it (only) would if an existing rail line needs to be entered into OSM, then might be repurposed as a light_rail line.  If there is no rail to be repurposed, and it is brand-new-from-scratch passenger rail, skip that first part and wrangle when it is best to first enter "proposed," then "construction" and finally (as ribbons are cut), turning those infrastructure into passenger service lines.  For trains and light_rail/tram these are slightly different:  for trains, you have BOTH a route=railway relation and a route=train relation, for light_rail, you can do it with a single relation that represents both the physical / infrastructure elements of the rail AND the passenger-oriented members of the single route=light_rail relation (like platforms and stop_area members).