Skip side-band-64k TCP server tests on windows if cgit not >= 1.9.3.

Signed-off-by: Jelmer Vernooĳ <jelmer@samba.org>
Add .gitattributes files to force fast-export data for tests to checkout with lf line endings.

Signed-off-by: Jelmer Vernooĳ <jelmer@samba.org>