title: react-native run-android Could not find com.android.tools.build:gradle:3.0.1
body: <pre><code>apple@mosesdeMacBook-Pro:~/Desktop/sxtbdemo2$ react-native run-android
  Scanning folders for symlinks in /Users/apple/Desktop/sxtbdemo2/node_modules (8ms)
  JS server already running.
  Building and installing the app on the device (cd android &amp;&amp; ./gradlew installDebug)...
  
  FAILURE: Build failed with an exception.
  
  What went wrong:
  A problem occurred configuring root project 'sxtbdemo2'.
  Could not resolve all files for configuration ':classpath'.
  Could not find com.android.tools.build:gradle:3.0.1.
   Searched in the following locations:
       https://jcenter.bintray.com/com/android/tools/build/gradle/3.0.1/gradle-3.0.1.pom
       https://jcenter.bintray.com/com/android/tools/build/gradle/3.0.1/gradle-3.0.1.jar
   Required by:
       project :
  
   Try:
       Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
  Get more help at https://help.gradle.org
  
  BUILD FAILED in 12s
  Could not install the app on the device, read the error above for details.
  Make sure you have an Android emulator running or a device connected and have set up your Android development environment: https://facebook.github.io/react-native/docs/android-setup.html
  </code></pre>