[fudge] give a better error message for missing test files
[fudge] give a better error message for missing test files

cygx/roast,skids/roast,dogbert17/roast,b2gills/roast,zostay/roast,zostay/roast,b2gills/roast,niner/roast,niner/roast,dankogai/roast,zostay/roast,dogbert17/roast,laben/roast,niner/roast,skids/roast,b2gills/roast,laben/roast,bitrauser/roast,cygx/roast,dankogai/roast,skids/roast,perl6/roast,dankogai/roast,laben/roast,bitrauser/roast,cygx/roast