Prevent setUp from deleting psiturk-example folder.
Prevent setUp from deleting psiturk-example folder.

michaelpacer/psiTurk,suchow/psiTurk,rbtrace/psiTurk,michaelpacer/psiTurk,berkeley-cocosci/psiTurk,johnmcdonnell/psiTurk,berkeley-cocosci/psiTurk,pfeyz/psiTurk,mshvartsman/psiTurk,suchow/psiTurk,johnmcdonnell/psiTurk,mshvartsman/psiTurk,berkeley-cocosci/psiTurk,michaelpacer/psiTurk,andyh616/psiTurk,mshvartsman/psiTurk,NYUCCL/psiTurk,pfeyz/psiTurk,NYUCCL/psiTurk,pfeyz/psiTurk,andyh616/psiTurk,kachergis/psiTurk,kachergis/psiTurk,andyh616/psiTurk,kachergis/psiTurk,NYUCCL/psiTurk,rbtrace/psiTurk,suchow/psiTurk,johnmcdonnell/psiTurk,rbtrace/psiTurk