vfs_fruit: add option veto_appledouble

vfs_fruit: add option veto_appledouble

vfs_fruit adds a wildcard path "._*" to the vetolist in order to prevent
client access to ._ AppleDouble files created internally by vfs_fruit
for storing the Mac resource fork stream.

Unfortunately there are legitimite use cases where an OS X client may
want to use such filenames, extracting ZIP archives (where the archive
contains ._ files) being one of them.

A possible simple solution to this problem would be to not veto ._ files
in the first place, even though that exposes internally created ._ files
which the client shouldn't be able to access.

Bug: https://bugzilla.samba.org/show_bug.cgi?id=11305

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Autobuild-User(master): Ralph Böhme <slow@samba.org>
Autobuild-Date(master): Tue Jun  9 14:48:14 CEST 2015 on sn-devel-104