title: SDK Manager in Android studio 3.0.1
body: <p>I download and install android studio 3.0.1 from developer.android.com. but that package did not have any sdk manager. before I had android studio 2.3.1 and I had sdk 25 for that . now I uninstall 2.3.1 and install 3.0.1. 
  which version of SDK I should download for android studio 3.0.1 and how I should install it? I have a picture from my gradle in android studio 3.0:</p>
  
  <p><img src="https://i.stack.imgur.com/eAtit.png"></p>