Add another box to fix plugged dialog in settings manager
Initial work for a new battery indicator plugin

This patch moves some code around, mostly putting shared stuff into
power-common inside common/. It also creates a new plugin to monitor
all the batteries in one icon on the panel rather than multiple icons
inside the system tray. It also removes the power-info application
as that will be moved inside the newly reworked settings dialog.
Update when device properties change
Add code for devices being removed
Change battery icons to reflect its status
Change the panel icon back

Dynamically changing the icon in the panel itself looks horrible.
Revert and improve it later.
Remove the old system tray icons
Fix a crash on upower version change

Also put more trace/dbg messages in place so it's easy to track
these issues when upower breaks itself again in the future.
Update line power when state changes
Suspend was dropped in Upower 0.9.23
Panel icon shows AC power status now
Fix memory leaks, add sane defaults for panel icon
Add preferences to popup window
Comment some of the code
MAX(xthickness, xthickness) makes no sense
Close the popup when preferences selected
Make the Preferences... button flat to fit in
Selection follows mouse for treeview
Move Preferences button to the left
Merge branch 'power-indicator' of github.com:EricKoegel/xfce4-power-manager into power-indicator