support tar.gz where files are prefixed by "./"

[davidB]

To allow self_update to use .bin_name("f1.txt") on : archive are created like:

tar -czvf t_archive.tar.gz -C t_archive .
a .
a ./f1.txt

like (existing) for archive created like:

cd t_archive
tar -czvf ../t_archive-2.tar.gz  *
a f1.txt

PS: calling .bin_name("./f1.txt") failed

[davidB]

the error on windows is random, sometime present, sometime no-error and in various place. I'm not a windows FS expert. Any suggestion ?