Fixed vtl:s without version not working
Fixed vtl:s without version not working

core/db/locator.py:
  - guess_extension_from_contents:
    int conversion need to check for TypeError

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