Bumped expiry date to 1 September 2017.

briar-android/src/main/java/org/briarproject/briar/android/splash/SplashScreenActivity.java

@@ -30,8 +30,8 @@ public class SplashScreenActivity extends BaseActivity {
 	private static final Logger LOG =
 			Logger.getLogger(SplashScreenActivity.class.getName());
 
-	// This build expires on 1 July 2017
-	private static final long EXPIRY_DATE = 1498863600 * 1000L;
+	// This build expires on 1 September 2017
+	private static final long EXPIRY_DATE = 1504220400 * 1000L;
 
 	@Inject
 	protected ConfigController configController;