add change log and update to 2.4.0

CHANGELOG

@@ -1,5 +1,9 @@
 ## THE CHANGELOG
 
+
+#### 2.4.0-alpha
+- support 2.4.0-alpha.1 agora video sdk android-2.4.0 / iOS-2.4.0.1 and add sendMessage support in the same channel.
+
 #### 2.3.3-alpha
 - support agora video sdk 2.3.3
 - release 2.3.3-alpha.3

package.json

@@ -1,6 +1,6 @@
 {
   "name": "react-native-agora",
-  "version": "2.3.3-alpha.7",
+  "version": "2.4.0-alpha-1",
   "description": "React Native around the Agora RTC SDKs for Android and iOS agora",
   "summary": "agora native sdk for react-native",
   "main": "lib/index.js",