[Cin] Images sequence

[Andrea paz]

I think it is a problem of absolute or relative paths: the file-list
is formed correctly, but references to image-frames are missing due to
unrecognized paths. I had already found the problem previously:
https://lists.cinelerra-gg.org/pipermail/cin/2021-December/004335.html
Maybe there has been some change (in ffmpeg or in CinGG or in image2)
regarding the management of paths?