Problem
When you add a new attendee, currently the list of attendees will get replaced by a spinner, then they will all reappear. It looks a bit funky.
Changes Made
Now, the existing list will stay there, a loading spinner will appear, then the new attendee will get added to the bottom of the list
Also, there is better error handling: error for adding the same user to the roadtrip twice:
Problem When you add a new attendee, currently the list of attendees will get replaced by a spinner, then they will all reappear. It looks a bit funky.
Changes Made Now, the existing list will stay there, a loading spinner will appear, then the new attendee will get added to the bottom of the list
Also, there is better error handling: error for adding the same user to the roadtrip twice:
Closes #83