- Reverting unix.py to use process.poll() in a loop to see if using process.wait()   was really causing memory allocation problems.
- Reverting unix.py to use process.poll() in a loop to see if using process.wait()
  was really causing memory allocation problems.

celiafish/VisTrails,VisTrails/VisTrails,celiafish/VisTrails,hjanime/VisTrails,minesense/VisTrails,minesense/VisTrails,VisTrails/VisTrails,hjanime/VisTrails,hjanime/VisTrails,VisTrails/VisTrails,Nikea/VisTrails,VisTrails/VisTrails,Nikea/VisTrails,minesense/VisTrails,hjanime/VisTrails,minesense/VisTrails,hjanime/VisTrails,VisTrails/VisTrails,minesense/VisTrails,celiafish/VisTrails,celiafish/VisTrails,Nikea/VisTrails,Nikea/VisTrails