Rework pkgdir-tool

Rework pkgdir-tool

For several issue(performace, code consistency, ...), the pkgdir-tool is
reworked.

The app-installer calls security-manager api just once for labeling
skel directories, not for each users.
And the pkgdir-tool copies those labeled directories to each user's home
directory.

The pkgdir-tool doesn't have setuid bit no more(because of security issue),
so it will be launched by dbus activation.
(It still needs root privilege for writing permission to user directories)

Requires:
 - https://review.tizen.org/gerrit/68140
 - https://review.tizen.org/gerrit/68294

Change-Id: Ib96c41f08d681443c5993bedd3fcf4f1c91db8c3
Signed-off-by: Sangyoon Jang <s89.jang@samsung.com>