Merge pull request #1031 from RocketChat/chore/increment_build_beta4

[CHORE] Increment build beta number to 4

app/build.gradle

@@ -13,8 +13,8 @@ android {
         applicationId "chat.rocket.android"
         minSdkVersion 21
         targetSdkVersion versions.targetSdk
-        versionCode 2003
-        versionName "2.0.0-beta3"
+        versionCode 2004
+        versionName "2.0.0-beta4"
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         multiDexEnabled true
     }