Switch to new event system (#9)

* `SignalEvents` and `synchronized` mode for `EventsListenable`

* cascade syntax

* clean up

* `RoomEvents`

* `ParticipantEvents`

* all events implemented

* make it compile with M1 macs

* dispose logic

* cleaner connect logic

* ask to publish

* fix initial EngineTrackAddedEvent glitch

* fix unpublishTrack bug

* clean up

* better events docs

* organize event types

* clean up

* cleaner wait logic

* wait for event instead of using Completer

* notifyListeners

example/ios/Podfile.lock

@@ -2,14 +2,14 @@ PODS:
   - Flutter (1.0.0)
   - flutter_webrtc (0.2.2):
     - Flutter
-    - GoogleWebRTC (= 1.1.31999)
     - Libyuv (= 1703)
-  - GoogleWebRTC (1.1.31999)
+    - WebRTC-SDK (= 92.4515.05)
   - Libyuv (1703)
   - path_provider (0.0.1):
     - Flutter
   - shared_preferences (0.0.1):
     - Flutter
+  - WebRTC-SDK (92.4515.05)
 
 DEPENDENCIES:
   - Flutter (from `Flutter`)
@@ -19,8 +19,8 @@ DEPENDENCIES:
 
 SPEC REPOS:
   trunk:
-    - GoogleWebRTC
     - Libyuv
+    - WebRTC-SDK
 
 EXTERNAL SOURCES:
   Flutter:
@@ -33,13 +33,13 @@ EXTERNAL SOURCES:
     :path: ".symlinks/plugins/shared_preferences/ios"
 
 SPEC CHECKSUMS:
-  Flutter: 434fef37c0980e73bb6479ef766c45957d4b510c
-  flutter_webrtc: 39898454258b54ba51996850d5da8d5d53bf1524
-  GoogleWebRTC: b39a78c4f5cc6b0323415b9233db03a2faa7b0f0
+  Flutter: 50d75fe2f02b26cc09d224853bb45737f8b3214a
+  flutter_webrtc: c0cb88c7cbd057e6e667ab1560e10c74e2ceb65b
   Libyuv: 5f79ced0ee66e60a612ca97de1e6ccacd187a437
-  path_provider: abfe2b5c733d04e238b0d8691db0cfd63a27a93c
-  shared_preferences: af6bfa751691cdc24be3045c43ec037377ada40d
+  path_provider: d1e9807085df1f9cc9318206cd649dc0b76be3de
+  shared_preferences: 5033afbb22d372e15aff8ff766df9021b845f273
+  WebRTC-SDK: 7c76a541dbbffb0fc212aeb9902ec45a43c23996
 
-PODFILE CHECKSUM: 6055d9653e1011c0b3b671abb92cdea979357e63
+PODFILE CHECKSUM: 82aed1035f46bfa5b522f0d0dbf4730f17ec65ff
 
-COCOAPODS: 1.10.1
+COCOAPODS: 1.11.2