Remove unused code. (#113)

Author: robxyy

lib/android/src/main/java/com/airbnb/android/react/navigation/ReactNativeActivity.java

@@ -1,6 +1,5 @@
 package com.airbnb.android.react.navigation;
 
-import android.os.Build;
 import android.os.Bundle;
 import android.os.Handler;
 import android.util.Log;

lib/android/src/main/java/com/airbnb/android/react/navigation/ReactToolbar.java

@@ -6,7 +6,6 @@
 import android.net.Uri;
 import android.support.v7.widget.Toolbar;
 import android.util.AttributeSet;
-import android.util.Log;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;

lib/android/src/main/java/com/airbnb/android/react/navigation/ScreenCoordinatorLayout.java

@@ -8,8 +8,6 @@
 import android.support.v4.app.FragmentManager;
 import android.util.AttributeSet;
 import android.view.View;
-import android.view.ViewGroup;
-import android.view.animation.Animation;
 import android.widget.FrameLayout;
 
 import java.util.ArrayList;

lib/android/src/main/java/com/airbnb/android/react/navigation/TabBarView.java

@@ -1,8 +1,6 @@
 package com.airbnb.android.react.navigation;
 
 import android.content.Context;
-import android.os.Bundle;
-import android.support.v4.app.Fragment;
 import android.util.AttributeSet;
 import android.view.View;
 import android.view.ViewGroup;

lib/android/src/main/java/com/airbnb/android/react/navigation/TabBarViewManager.java

@@ -5,7 +5,6 @@
 import com.facebook.react.uimanager.ThemedReactContext;
 import com.facebook.react.uimanager.ViewGroupManager;
 import com.facebook.react.uimanager.annotations.ReactProp;
-import com.facebook.react.views.view.ReactViewGroup;
 
 public class TabBarViewManager extends ViewGroupManager<TabBarView> {
   private static final String TAG = "TabBarViewManager";