Broadcasting mode for instructors

[pbanaszkiewicz]

Hi @drio

(refs #3)

I worked on broadcasting mode a little bit. Thanks to PeerJS "one way calls" it was possible to make this broadcasting mode. However, I'm very unhappy with how events are propagated through Pitt and I really want to drop socket.io and to switch to WAMP.

I wrote a blogpost about the changes.

There are some bugs in the code, unfortunately. And lots and lots of console.log debugging debris.

Some one the bugs include:

• for the broadcasting mode to work instructor have to "show up" last - ie. after all their students show up. That's because the code for instructor emits an event that's crucial for broadcasting when the instructor loads their page.
• after broadcasting session is over, students have to reload their pages in order to receive a new broadcast. Otherwise there's and error occurring in PeerJS lib. I think it's connected to some HTML tag missing from the DOM, but I didn't investigate further.

[drio]

Comments on this in #1.

[drio]

Closing since all this will be reimplemented on the WAMP pr.