[openrailwaymap] Re: Tagging decision: ebicab, atc, convel, zub123

If we are going to retag things, I still think that defining a railway:train_protection=* system is much less work. Think about your PRs: how many railway:foobar=no tags do you want to get a "proper" selector for "no system". We should leave the already established systems as they are for now, to avoid a mass conversion, and only use this for "new" systems for the moment. I also think we should consider adding country prefixes for these tagging systems, it's likely that common names like "ATP" or something like that may show up more than once on the planet, so we would get DE:PZB. And when we are thinking about, lets just think one step ahead: how do we want to tag different levels or versions of the same system, especially if they may be installed at the same time? So, at the end, I think we should end up with something like: railway:train_protection=DE:PZB;DE:LZB;ETCS:2.3 And for the systems from the previous mail that would be something like: NO:ATC, SE:ATC, PT:CONVEL, FI:JKV At the end it should probably be DK:ATC instead of DK:ZUB123 as we usually use the local names in OSM.