Icon: Construction

[benlk]

• [x] Add an icon file (SVG?) for the construction logos
• [x] Hide construction items from the homepage view

Bonus:

• [ ] Add a "construction zone", which is a path or shape requiring construction, which is shaded on the map, and displays an icon. These should be included in the construction items list
• [ ] Add an "order" parameter for items on the page, to allow sorting of items in the display lists by line order.

[benlk]

https://commons.wikimedia.org/wiki/File:MUTCD_G20-5aP.svg

[benlk]

🚧

[benlk]

Construction zone is in https://github.com/benlk/columbus-regional-rail/issues/16

Order is by editing the JSON, for now.