edit-node:Launching shell before the state of selinux reset back

Previously when using --shell option, edit-node change to permissive on the
build machine if it's enforcing, then reset back.Launching shell in the end.
Now fix it launching shell before the state of selinux reset back
Aslo the same action for set_password/ssh_keys/uid/gid

Change-Id: I36da71464931f8c8bdd202dff63b1779f8218f12
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1016526
Signed-off-by: hadong <hadong0720@gmail.com>