* Makefile.in (sysconfdir): Define.
(install): Create $(sysconfdir)/postinstall dir. Install postinstall
script into it.
* path.cc: Add temorary comments to note later function removal.
(conv_fstab_spaces): New inline function to handle \040 to space
conversion.
(struct opt): Add "system" and "user" mount options.
(mount_info::from_fstab_line): Only allow # to start a comment at
the beginning of the line. Call conv_fstab_spaces on native_path and
posix_path fields. Don't enforce system mounts in /etc/fstab.
Drop last argument in call to add_item.
(mount_info::from_fstab): Create a default cygdrive entry. Load
user mount points from fstab.<username> instead of fstab.<sid>.
(mount_info::read_mounts): Drop last argument in call to add_item.
(mount_info::add_reg_mount): Remove.
(mount_info::del_reg_mount): Remove.
(mount_info::write_cygdrive_info): Rename from
mount_info::write_cygdrive_info_to_registry. Don't write to registry.
Disallow to overwrite a system cygdrive prefix.
(mount_info::remove_cygdrive_info_from_registry): Remove.
(mount_info::get_cygdrive_info): Just fetch current cygdrive prefix and
flags.
(mount_info::add_item): Drop last argument. Don't write to registry.
Disallow to overwrite a system mount point.
(mount_info::del_item): Drop last argument. Don't write to registry.
Disallow to remove a system mount point.
(mount): Enforce user mount.
(cygwin_umount): Ditto.
* shared_info.h (mount_info::add_item): Drop last argument.
(mount_info::del_item): Ditto.
(mount_info::add_reg_mount): Remove.
(mount_info::del_reg_mount): Remove.
(mount_info::write_cygdrive_info): Rename from
mount_info::write_cygdrive_info_to_registry.
(mount_info::remove_cygdrive_info_from_registry): Remove.
