UMDP3 checker can't be passed a single file to check #221

When run in fullcheck mode, i.e. bypassing a CMS check for changed files, it was assumed that if a filename were provided with "-p ///" that it would check that file.

It doesn't, the 'glob' appears to be returning an empty list.
Perhaps this should be altered to check if the path is to a single file and return that.