UX: Detect when collaborator is offline and force refresh

When a user's internet connection is dropped, sometimes it reconnects to a different network. This causes the real time web socket session to be dropped, causing a mismatch between what each collaborator sees in the model. By forcing page refresh whenever a network connection is reestablished, we can ensure that models remain in sync between collaborators. If this happens, you will see the following message on your screen: You’re offline We’ve detected a network issue. You can continue making edits when you’re back online.