Create a "create shareable link" button

[rpruim]

We have a way to load a schedule from a CSV provided in the URL. That's great for chairs who know how to export the schedule, save it somewhere public, and create the necessary URL.

But for typical chairs, it would be much easier if they could just click on a button and get the URL they need.

The most challenging part of this is likely the data storage aspect. We would need a place to save the exported schedule so we can serve it back.

Even better, of course, would be to have some sort of data back-end to this. Think of this as a poor chairs version.

An even poorer version (but still useful) would be that if the load from URL option is used, then it is possible to get that URL back. That would at least allow chairs to confirm that the file loads and easily get the URL for forwarding. Right now, the URL is wiped as soon as the schedule is loaded. Pehaps this option could disappear if the schedule is modified, just to make sure that people are forwarding what they intend to forward.