Prepare release 0.2.3 (4003)

Change-Id: I785c3c51ba59c7528e664eff06de4b432604ecdf
diff --git a/app/build.gradle b/app/build.gradle
index f86e645..ab592cb 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -10,8 +10,8 @@
         applicationId "net.named_data.nfd"
         minSdkVersion 15
         targetSdkVersion 19
-        versionCode 4002
-        versionName "0.2.2 (NFD 0.5.0)"
+        versionCode 4003
+        versionName "0.2.3 (NFD 0.5.0)"
     }
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_7