Add shutdown/reboot functionality for systemd (Bug 10167)

based on the xfce4-session implementation [1]
[1] http://git.xfce.org/xfce/xfce4-session/commit/?id=ae28aef315a7a6b90f1649ce6d1f30b842791cbf

Guido Berhoerster assisted by allowing polkit support without
needing systemd.

Eric Koegel changed the xfpm-systemd.c code to use xfpm's internal
polkit code rather than require an external dependancy so the checks
can be done at runtime.
Fix empty systray icon in some panels on battery removal and addition

Unreferencing a GtkStatusIcon is not enough to get rid of it entirely.

This fixes these bugs:

    https://bugzilla.xfce.org/show_bug.cgi?id=7603
    http://bugzilla.xfce.org/show_bug.cgi?id=8424
    https://bugs.launchpad.net/ubuntu/+source/lxpanel/+bug/846878
    https://bugzilla.redhat.com/show_bug.cgi?id=765726

Signed-off-by: Eric Koegel <eric.koegel@gmail.com>
Display power percentage

This is particularly relevant for Logitech Unifying devices.

My test device was a Logitech M185 wireless mouse, which has no power
related properties except for "percentage".

Signed-off-by: Eric Koegel <eric.koegel@gmail.com>
Fix status icon for devices other than battery and ups (Bug 8188)

xfpm_battery_refresh_icon incorrectly adds an additional dash to
the icon prefix when the device is not a battery or a ups.

Additionally, this patch correctly shows the icon when the device
reports that it is charging.

This patch only combines the patches submitted by
Daniel Schubert and Dean Montgomery.
Update to XFCE_PANEL_PLUGIN_REGISTER

Updates from the per-4.8 panel registration method. Also updates
the gtk about function for the new field and updates the makefile
for the plugin.
Add support for keyboard backlight control (Bug 10470)

I have enhanced xfce4-power-manager to support backlit keyboard brightness
control through keyboard brightness keys. It uses
org.freedesktop.UPower.KbdBacklight interface for increasing or decreasing
the keyboard backlight brightness and binds with keys
XF86XK_KbdBrightnessUp and XF86XK_KbdBrightnessDown.

This feature is useful when the firmware does not handle the keyboard
brightness control automatically. For example MacBook Pro leaves it to the
OS to control the keyboard brightness through special keys. With this
change, I can light up the keyboard on MacBook Pro and control its
brightness through the special keys.

I have also tested this on Lenovo X1 Carbon where the keyboard brightness
is automatically handled by the firmware and this enhancement steps aside
without interfering.
Don't allow systemd to handle suspend/hibernate events.

Signed-off-by: Eric Koegel <eric.koegel@gmail.com>
xfpm-power-info: add current percentage of batteries

a bluetooth mouse's battery might not have any Energy* properties (all
zero), but a Percentage property, so it might be useful to show that.

Signed-off-by: Eric Koegel <eric.koegel@gmail.com>
xfpm-battery: do not show an icon for HID devices

my bluetooth mouse always shows up as a second battery which is not too
useful -- ignore devices starting with "hid-"
TODO: check if this affects UPSs.

Signed-off-by: Eric Koegel <eric.koegel@gmail.com>
Update xfce4-session lock-screen setting

When xfpm changes it's lock-screen setting, it will also attempt
to update xfce4-session. Additionally, xfpm will watch session's
lock-screen setting and update its own. This way there is one
single setting for both programs in the future, however xfpm will
continue to function stand-alone.
Use the online docs for help

Point to the online docs for xfpm's help. This also fixes it where
the help button was causing the preferences dialog to quit. Now
xfpm will also display the help page when plugged into the settings
dialog. This patch removes the old local docs as well.
Add xfpm-backlight.c to potfiles
Remove the doc configure deps
I18n: Update translation bg (100%).

217 translated messages.

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I18n: Update translation fr (99%).

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I18n: Update translation kk (100%).

217 translated messages.

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I18n: Update translation fr (100%).

217 translated messages.

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I18n: Update translation sv (100%).

217 translated messages.

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I18n: Update translation en_AU (100%).

217 translated messages.

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I18n: Update translation th (100%).

217 translated messages.

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