title: Android studio 2.3 canary missing 'Launch Standalone SDK Manager' option in 'SDK Manager'
body: <p>I inadvertently accepted android studio's upgrade suggestion to 2.3 (canary), although I had always had it set to check for the developer channel, not canary, somehow that got switched. Now I no longer have a 'Launch Standalone SDK Manager' option in my 'SDK Manager' window. </p>
  
  <p>I liked the standalone manager for various reasons, including that it suggested what needed to be downloaded and upgraded. The regular sdk manager lists a lot of things I expect I don't need like 'CMake', 'LLDB', 'Constraint Layout for Android', 'Solver for ConstraintLayout', 'Google Play APK Expansion Library' ('Google Play APK Expansion Library rev 3' is already installed, so do I need this too?), etc.</p>
  
  <p>Is the standalone sdk manager unavailable for 2.3 canary 2, or is there something more I need to do to get it?</p>