Cairo-Dock Plug-ins 3.1.1

* Plug-ins: [by Fabrice Rey & Matthieu Baerts]
 * Application Menu:
  * Recent-Menu was on a wrong section after an update of the menu (e.g. when a program was added/removed)
  * Menu: file name: firstly checked with XDG_MENU_PREFIX env variable (e.g. to use 'xfce-applications.menu' instead of 'applications.menu' in XFCE)
 * Clock: we need to include 'gdk/gdkkeysyms.h' for older versions of Gtk2
 * Dialogues: avoid using blocking dialogues (except if it's needed)
 * Dock-rendering: clean the dock correctly when switching from a 'Panel' view to another one.
 * Keyboard:
  * Forgot to replace the old (and temporally) emblems for CapsLock/NumLock (thanks to Freb ;) )
  * Gtk3: Used GDK functions to get the num/caps lock states because it seems it doesn't work very well with xKlavier functions with recent versions...
  * Clean old code
 * MusicPlayer:
  * Songs dropped on the icon were not enqueued
  * Mpris2: some players are not able to give a 'int64' value for 'mpris:length'
  * If the music player gives us a '.desktop' filename, check first if it's a valid name before doing something more (e.g. Amarok give us a wrong name and then, it was not possible to re-launch Amarok from this applet)
 * Shortcuts:
  * Fixed a possible crash if the removed icon was at the beginning of the list
  * Allowed shortcuts like 'Browse Network', 'Browse recent files', and 'Open Trash' to quickly open the corresponding URI
 * Sound Control:
  * Alsa backend: Handled this case: the default card is not the card that we want to control
  * When setting the volume while the output is mute, unmute it
 * Status-Notifier:
  * Fixed a typo with the version of its .conf file
  * Don't add an empty icon path to the icons theme
 * Third-party applet: Store the icon name in order to use a new icon if the icon theme changes
 * Misc.:
  * Compilation: Status-Notifier: fixed a compilation error if 'indicator' is not found.
  * Updated translations