title: android studio 1.2 gradle is very slow
body: <p>it's been a while that I'm using Android Studio, and up until now I was using 1.0.1, 
  gradle was a bit slow, around 1.5 minute for assembleDebug (my project is really big!)
  but today I updated my AS to 1.2 and now same process takes about 7 to 10 minutes, and sometimes even with no result!</p>
  
  <p>is there any setting I have to change to make it faster ?
  honestly taking 10 minute for every debug run is a nightmare !</p>
  
  <p>Also most of the time, my cpu usage is arround 10 percent! (it is actually idle!)
  cause before when gradle was working it was on 100% almost all the time </p>