BREAKING CHANGE: Update API for connection, communication channel state and is browser value (#14)

* refactor(lib, example, example_full): use streams for communication channel and is ios browser

* feat: add abstract toJson() to message

* refactor: add deprecations for nearby_service

* feat(example): update main.dart

* feat(nearby_service): add comments

* feat(nearby_service_platform_interface): add deprecation to getConnectedDeviceStream

* feat(nearby_service/message): add concrete implementation for toJson()

* feat(nearby_service/android): add deprecations

* fix(nearby_service/android): reset check for android device

* fix(nearby_service/ios): change ios service to deprecations variant

* chore(nearby_service): edit deprecation messages

* chore: update gitignore

* doc: add CONTRIBUTING file

* doc: update CONTRIBUTING file

* chore: update CONTRIBUTING.md

* chore: update CONTRIBUTING.md

* chore: version 0.1.0

* fix(example_full): move startListeningCommunicationChannelState() upper

lib/nearby_service_platform_interface.dart

@@ -48,11 +48,21 @@ abstract class NearbyServicePlatform extends PlatformInterface {
     throw UnimplementedError('streamPeers() has not been implemented.');
   }
 
+  @Deprecated('Use getConnectedDeviceStreamById instead')
   Stream<NearbyDevice?> getConnectedDeviceStream(NearbyDevice device) {
     throw UnimplementedError(
         'getConnectedDeviceStream() has not been implemented.');
   }
 
+  Stream<NearbyDevice?> getConnectedDeviceStreamById(String deviceId) {
+    throw UnimplementedError(
+      'getConnectedDeviceStreamById() has not been implemented.',
+    );
+  }
+
+  @Deprecated(
+    'This method will be removed. Method disconnect is platform-specific and you should use NearbyServiceIOSPlatform.disconnectById or NearbyServiceAndroidPlatform.disconnectById instead.',
+  )
   Future<bool> disconnect(NearbyDevice device) {
     throw UnimplementedError('disconnect() has not been implemented.');
   }