Handle non-absolute path names in sql file.
Handle non-absolute path names in sql file.

The ZIMAGE table has a PATHSTRING field for the filename, and I thought
it always held an absolute pathname for "linked" images.  Apparently,
it can also hold just the filename, rather than the complete path, in
which case the filename is within DATABASE.noindex, but with a different
extension than the usual ".dcm" that is used with PATHNUMBER.  Note that
everything I've added here is the result of reverse engineering...

hendradarwin/vtk-dicom,hendradarwin/vtk-dicom,dgobbi/vtk-dicom,hendradarwin/vtk-dicom,dgobbi/vtk-dicom,dgobbi/vtk-dicom