cdc and log: Add a log history and window.
When the dock is started with 'cdc service dock', you can now later call 'cdc service log' and get access to all your dock logging history (hardcoded limit to 12h for now).
+ added exec commands API to the logger (to grab and log output).
+ improved the handling of the gtk main loop. Now need to add the 'gtk' tag to enable optional gtk dependencies (including the log window).
+ applets now also work in the external system applet dir (/usr/share/cairo-dock/plug-ins/Dbus/third-party)
+ cdc can now accept shortcuts for most used actions (c: config, d: debug, r: restart, s: service, u: upload)
+ and a little more documentation.
DiskFree: Updated the partitions filter to remove all /dev/* and /sys/* (works better on archlinux)
Update: Splitted the build job to the new libs/packages/build (+update, doc and cleanup).