Currently, this package can not be installed while using standard path
of busybox, because binary killall wants to be installed on the same
location as busybox.

Collision:
• /usr/bin/killall: busybox (new-file), psmisc (existing-file)

Many of these binaries, which provides alternatives were moved to
folder /usr/libexec like wget, sed, findutils, less.
So I moved killall to /usr/libexec and others leave in touch and added
ALTERNATIVES for it, because preinstall script is no longer necessary.

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>
(cherry picked from commit d8969e0f)