#292 lxterminal: add dependency on libutempter

[jb1234abcd]

LXDE's lxterminal does not update utmp/wtmp.
To be consistent with other DEs and their X terminals. GNOME and XFCE terminals do it, xterm/uxterm do it.
Some users or sysadmins set them up as login terminals, scripts may rely on consistent output of "w', 'who', 'last' entries.
Some users/sysadmins may consider it a semi-security issue.

xterm:
$ ldd which xterm
...
libutempter.so.0 => /usr/lib/libutempter.so.0 (0x00007f658d8b3000)
...
$ w
12:47:36 up 2 days, 8:17, 2 users, load average: 0.00, 0.03, 0.08
USER TTY LOGIN@ IDLE JCPU PCPU WHAT
jb tty1 Mon04 2days 24:51 0.00s xinit /home/jb/.xinitrc -- /hom
jb pts/2 12:45 0.00s 0.02s 0.00s w

lxterminal:
$ w
12:44:30 up 2 days, 8:14, 1 user, load average: 0.03, 0.05, 0.10
USER TTY LOGIN@ IDLE JCPU PCPU WHAT
jb tty1 Mon04 2days 24:42 0.00s xinit /home/jb/.xinitrc -- /hom