Adds upgrade code for password dialog
Adds upgrade code for password dialog

When upgrading DBConnection from 0.0.3 to 0.1.0, just assume a password
is needed and add a dialog module to ask for it. Since only MySQL and
PostgreSQL were supported, I think this is reasonable.

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