wpt editor: Automated loading of route name in use + unused alt route names

[michihdeu]

Once we can load the wpt file from Git, see #372 the next step would be loading info about route names and provide the info in wpt editor.

• The route name should be displayed
• Alt route names should be displayed
• The route names should indicate (maybe text in red like with labels in use) if it is used*

https://travelmapping.net/logs/listnamesinuse.log
https://travelmapping.net/logs/unusedaltroutenames.log

*e.g. it could be possible that only the alt route name is in use but the regular name is not in use.

[yakra]

Should something in the domain of editing CSVs really be included in the WPT editor?

[michihdeu]

Why not? It would help maintaining hwy data.