Add OpenHistoricalMap support

[upintheairsheep]

OpenHistoricalMap is a version of OpenStreetMap that maps out historical places. Contributing is almost the same as in OSM but you need to add the date of creation and the date of destruction if applicable, and you need a slider to change the date.

[1ec5]

Neat, I could see myself using Go Map!! while out hunting for sidewalk marks.

As noted above, the API is exactly the same and the presets are nearly identical with a few customizations and a special date field type (OpenHistoricalMap/iD#185 OpenHistoricalMap/iD#187). We’ll probably need to maintain a fork of id-tagging-schema in order for Go Map!! to use these customizations more easily, but it’s still feasible to use Go Map!! with OHM in their absence, just a bit less convenient.

[aredridel]

Ooh, I'd very much use this too around Salem, MA. So many historical sites to enter!

[bryceco]

Under Settings > Advanced there is a place to set the OSM server, and you can enter "https://www.openhistoricalmap.org" there.

There's an Easter egg where you can enter "dev" there to quickly switch to the OSM dev server, and you can leave it blank to switch back to the default server. It would be easy to also support an "ohm" shortcut, or better yet a menu to switch between the options.

Switching to a different set of presets could also be triggered off that.

[upintheairsheep]

It should support start and end dates as well

…

Sent from my Apple Watch

[bryceco]

It should support start and end dates as well

That's out of scope. It would make a good fork though, and if enough people used it then it could be merged later.

[1ec5]

Thanks for making this change. Hope you don’t mind that I spilled the beans about this forthcoming Easter egg in the OHM documentation. 😁

[bryceco]

@1ec5 You say to use api.openhistoricalmap.com, but it needs to be "www" (weirdly).

[1ec5]

Huh, that is weird. Fixed.