Utility app to help a user find out the events that happen in a meeting.

The way the checksum is calculated now is more similar to the other API calls,
specially setConfigXML. It uses the content type 'application/x-www-form-urlencoded'
so the information in the post body doesn't have to be converted from/to
js/string, preventing possible checksum errors in different programming
languages.

If a meeting has no events for too long (24 hours), remove the meeting
mapping to prevent too much data from being stored forever on redis.

It changes less than the internal meeting ID. An application can subscribe
to an external ID and use the hook for several different meetings that will
have the same external ID but different internal IDs.

Will try again a number of times for about 5min and then give up. On giving
up, the hook is removed.
And a few fixes for saving and loading data on redis.

Save hooks and meetingID mappings to redis and get them back when the
application starts.
Still missing a way to remove old data in case the app loses events (e.g.
a hook for a specific meeting might stay on redis forever if the app
lost the meeting_destroyed event).

It now creates and destroys hooks instead of creating and removing
subscriptions.

Hooks can be global, to receive events from all meetings, or can receive
events for a single meeting. Depends on whether the meetingID parameter is
informed or not in the hooks/subscribe API call.

Also improved the log messages a bit.

sending the externalMeetingId from bbb-web to bbb-apps, so bbb-apps can use it on redis pubsub message meeting_created_message

Simple signature done initially in a way similar to how bbb-web does it.

Will allow only one subscription to a given callback URL. If trying to
subscribe again to the same URL, will return success but with a message
saying the callback URL is duplicated, very similar to the response of
create when called multiple times.

Saving subscriptions to a local database for now.

To proxy API calls to the webhooks app.

It will receive API calls to deal with web hooks to make it independent from
other components such as bbb-web.

Added a SDP hack for Firefox to replace the 0.0.0.0 in the c line

Simple queue that retries to emit the callbacks in case they fail. A lot to
improve yet, but the basic is working.

First step toward allowing callbacks to be called for all meetings in a
server, not for only a single meeting. Will need to change the way data
is stored on redis to improve the webhooks app, but it already works the
way it is now.

Started using coffee-script, updated the libraries, and now it subscribes
to all channels under 'bigbluebutton:*' so we can receive all events that
happened and select the ones we want.

Changed the wording of the webrtc messages to make them easier to understand

Update to ICE handling

added a check to make sure that ICE negotiation has finished before showing that the call has been accepted in the UI

Stop the webrtc timeout timer when 'connecting' is received

added an additional fail case for the WebRTC audio